doc.dtx
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% Copyright (C) 1993-2021
% The LaTeX Project and any individual authors listed elsewhere
% in this file.
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%\catcode`\<=14
%<+package|shortvrb>\NeedsTeXFormat{LaTeX2e}[1994/12/01]
%<+package> \ProvidesPackage{doc}
%<+shortvrb>\ProvidesPackage{shortvrb}
%<+package|shortvrb> [2021/10/04 v2.1n
%<+package|shortvrb> Standard LaTeX documentation package (FMi)]
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%% Package `doc' to use with LaTeX 2e
%% Copyright (C) 1989-2020 Frank Mittelbach, all rights reserved.
%
%
% Version: Date: Changes:
%
% 1.0a 5.5.88 This is nothing but a collection of tests and
% hacks. It is certainly going to be greatly
% changed.
% Better not to use it!
% 1.5a and earlier... are not longer recorded
% 1.5b and higher... are documented with the (undocumented) \changes
% feature.
%\fi
% \changes{v1.5f}{1989/04/29}{Thanks to Brian who documented the
% \cs{changes} macro feature.}
% \changes{v1.5g}{1989/05/07}{MacroTopsep now called MacrocodeTopsep and
% new MacroTopsep added}
% \changes{v1.5h}{1989/05/17}{All lines shortened to <72 characters}
% \changes{v1.5j}{1989/06/09}{Corrections by Ron Whitney added}
% \changes{v1.5q}{1989/11/03}{`\ldots{}Listing macros renamed to
% `\ldots{}Input. Suggested by R. Wonneberger}
% \changes{v1.5w}{1990/02/05}{Counter codelineno renamed to CodelineNo}
% \changes{v1.9a}{1993/12/02}{Upgrade for LaTeX2e}
% \changes{v1.9d}{1993/12/20}{Protected changes entry.}
% \changes{v1.0p}{1994/05/21}{Use new error commands}
%
%
% \hyphenation{make-index}
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% \DoNotIndex{\@flushglue,\@gobble,\@input}
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%
% {\catcode`\p=12 \catcode`\t=12 ^^A hack used later on to print
% \gdef\dimenvalue#1pt{$#1$pt}} ^^A register values with a - sign
%
% \newcommand{\DOC}{\texttt{doc}}
%
% \changes{v1.9t}{1995/05/11}{Use \cs{GetFileInfo}}
% \GetFileInfo{doc.sty}
%
% \CheckSum{2213} ^^A % keep the checksum in this file
%
% \title{The \DOC{} and \texttt{shortvrb} Packages\thanks
% {This file has version number \fileversion{} dated \filedate{}.}}
% \author{Frank Mittelbach\thanks{Further commentary added at Royal
% Military College of Science by B. Hamilton Kelly; English
% translation of parts of the original German commentary
% provided by Andrew Mills; fairly substantial additions,
% particularly from \texttt{newdoc}, and
% documentation of post-v1.5q features added at v1.7a by Dave
% Love (SERC Daresbury Lab). Extraction of \texttt{shortvrb}
% package added by Joachim Schrod (TU~Darmstadt).}}
%
% \MaintainedByLaTeXTeam{latex}
% \maketitle
%
% \begin{abstract}
% This package contains the definitions that are necessary to
% format the documentation of package files. The package was
% developed in Mainz in cooperation with the Royal Military College
% of Science. This is an update which documents various changes
% and new features in \DOC{} and integrates the features of
% \textsf{newdoc}.
% \end{abstract}
%
% \newif\ifmulticols
% \IfFileExists{multicol.sty}{\multicolstrue}{}
%
% \ifmulticols
% \addtocontents{toc}{\protect\begin{multicols}{2}}
% \fi
%
% {\parskip 0pt ^^A We have to reset \parskip
% ^^A (bug in \LaTeX)
% \tableofcontents
% }
%
% \changes{v1.7a}{1992/02/25}{Miscellaneous small changes to the text}
%
% \ifmulticols
% \begin{multicols}{2}[\section*{Preface to version 1.7}]
% \else \section*{Preface to version 1.7} \fi
%
% This version of \texttt{doc.dtx} documents changes which have occurred
% since the last published version \cite{art:doc} but which have been
% present in distributed versions of \texttt{doc.sty} for some time. It
% also integrates the (undocumented) features of the distributed
% \texttt{newdoc.sty}.
%
% The following changes and additions have been made to the user
% interface since the published version~\cite{art:doc}. See
% \S\ref{sec:interface} for more details.
% \begin{description}
% \item[Driver mechanism] "\DocInput" is now used in the driver file
% to input possibly multiple independent \DOC{} files and \DOC{} no
% longer has to be the last package. "\IndexListing" is replaced
% by "\IndexInput";
% \item[Indexing] is controlled by "\PageIndex" and "\CodelineIndex",
% one of which must be specified to produce an index---there is no
% longer a "\makeindex" in the default "\DocstyleParms";
% \item[The \texttt{macro} environment] now takes as argument the
% macro name {\em with\/} the backslash;
% \item[Verbatim text] Newlines are now forbidden inside "\verb" and
% commands "\MakeShortVerb" and "\DeleteShortVerb" are provided for
% verbatim shorthand;
% \item[\texttt{\bslash par}] can now be used in "\DoNotIndex";
% \item[Checksum/character table support] for ensuring the integrity
% of distributions is added;
% \item[\texttt{\bslash printindex}] becomes "\PrintIndex";
% \item[\texttt{multicol.sty}] is no longer necessary to use \DOC{} or
% print the documentation (although it is recommended);
% \item[`Docstrip' modules] are recognised and formatted specially.
% \end{description}
%
% As well as adding some completely new stuff,
% the opportunity has been taken to add some commentary to the code
% formerly in \texttt{newdoc.sty} and that added after version 1.5k of
% \texttt{doc.sty}. Since (as noted in the sections concerned) this
% commentary wasn't written by Frank Mittelbach but the code was, it is
% probably {\em not\/} true in this case that ``if the code and
% comments disagree both are probably wrong''!
%
% \subsection*{Bugs}
%
% There are some known bugs in this version:
% \begin{itemize}
% \item The "\DoNotIndex" command doesn't work for some single
% character commands most noticeable "\%".
% \item The `General changes' glossary entry would come out after
% macro names with a leading "!" and possibly a leading |"|;
% \item If you have an old version of \textsf{makeindex} long "\changes"
% entries will come out strangely and you may find the section
% header amalgamated with the first changes entry. Try to get an
% up-to-date one (see p.~\pageref{makeindex:version});
% \item Because the accompanying \textsf{makeindex} style files support
% the inconsistent attribute specifications of older and newer
% versions \textsf{makeindex} always complains about three `unknown
% specifier's when sorting the index and changes entries.
% \item If "\MakeShortVerb" and "\DeleteShortVerb" are used with
% single character arguments, e.g., "{|}" instead of "{\|}" chaos
% may happen.
% \end{itemize}
% (Some `features' are documented below.)
%
% \subsection*{Wish list}
%
% \begin{itemize}
% \item Hooks to allow "\DescribeMacro" and "\DescribeEnv" to write
% out to a special file information about the package's `exported'
% definitions which they describe. This could subsequently be
% included in the \texttt{docstrip}ped \texttt{.sty} file in a
% suitable form for use by smart editors in command completion,
% spelling checking etc., based on the packages used in a document.
% This would need agreement on a `suitable form'. \item Indexing of
% the modules used in \texttt{docstrip}'s "%<" directives. I'm not
% sure how to index directives containing module combinations; \item
% Writing out bibliographic information about the package; \item Allow
% turning off use of the special font for, say, the next guarded
% block.
% \end{itemize}
%
% \ifmulticols
% \end{multicols}
%
% \begin{multicols}{2}[\medskip \rule{\textwidth}{.3pt}
% \section{Introduction}]
% \else
% \section{Introduction}
% \fi
%
% The \TeX{} macros which are described here allow definitions and
% documentation to be held in one and the same file. This has the
% advantage that normally very complicated instructions are made
% simpler to understand by comments inside the definition. In addition
% to this, updates are easier and only one source file needs to be
% changed. On the other hand, because of this, the package files are
% considerably longer: thus \TeX{} takes longer to load them. If this
% is a problem, there is an easy remedy: one needs only to run the
% \texttt{docstrip.tex} program that removes nearly all lines that begin
% with a
% percent sign.
%
% The idea of integrated documentation was born with the development
% of the \TeX{} program; it was crystallized in Pascal with the \Web{}
% system. The advantages of this method are plain to see (it's easy
% to make comparisons \cite{art:Knuthliterat}). Since this
% development, systems similar to \Web{} have been developed for other
% programming languages. But for one of the most complicated
% programming languages (\TeX) the documentation has however been
% neglected. The \TeX{} world seems to be divided between:---
% \begin{itemize} \item a couple of ``wizards'', who produce many
% lines of completely unreadable code ``off the cuff'', and \item many
% users who are amazed that it works just how they want it to do. Or
% rather, who despair that certain macros refuse to do what is
% expected of them.\end{itemize}
%
% I do not think that the \Web{} system is {\em the\/} reference work;
% on the contrary, it is a prototype which suffices for the
% development of programs within the \TeX{} world. It is sufficient,
% but not totally sufficient.\footnote{I know that this will be seen
% differently by a few people, but this product should not be seen as
% the finished product, at least as far as applications concerning
% \TeX{} are concerned. The long-standing debate over `multiple
% change files' shows this well.} As a result of \Web, new programming
% perspectives have been demonstrated; unfortunately, though, they
% haven't been developed further for other programming languages.
%
% The method of documentation of \TeX{} macros which I have introduced
% here should also only be taken as a first sketch. It is designed
% explicitly to run under \LaTeX{} alone. Not because I was of the
% opinion that this was the best starting point, but because from this
% starting point it was the quickest to develop.\footnote{This
% argument is a bad one, however, it is all too often trotted out.} As
% a result of this design decision, I had to move away from the
% concept of modularization; this was certainly a step backward.
%
% I would be happy if this article could spark off discussion over
% \TeX\ documentation. I can only advise anyone who thinks that they
% can cope without documentation to ``Stop Time'' until he or she
% completely understands the \AmSTeX{} source code.
%
%
%
%
%
% \subsection{Using the \DOC{} package}
%
% Just like any other package, invoke it by requesting it with a
% |\usepackage| command in the preamble. \textsf{Doc}'s use of
% |\reversemarginpars| may make it incompatible with some classes.
% \changes{v1.7a}{1992/02/25}{Altered usage info}
%
%
% \ifmulticols\end{multicols}\fi
%
%
% \section{The User Interface}\label{sec:interface}
% \subsection{The driver file}
%
% If one is going to document a set of macros with the \DOC{}
% package one has to prepare a special driver file which produces the
% formatted document. This driver file has the following
% characteristics:
%
% \noindent |\documentclass[|\meta{options}]^^A
% |{|\meta{document-class}|}|\\[1pt]
% |\usepackage{doc}|\\[3pt]
% \hspace*{10pt}\meta{preamble}\\[3pt]
% |\begin{document}|\\[3pt]
% \hspace*{10pt}\meta{special input commands}\\[3pt]
% |\end{document}|
%
% The \meta{document-class} might be any document class, I normally
% use \texttt{article}.
%
% In the \meta{preamble} one should place declarations which
% manipulate the behavior of the \DOC{} package like
% |\DisableCrossrefs| or |\OnlyDescription|.
%
% \DescribeMacro\DocInput \DescribeMacro\IndexInput
% Finally the \meta{special input commands} part should contain one or
% more |\DocInput|\meta{file name} and/or
% |\IndexInput|\meta{file name} commands. The
% |\DocInput| command is used for files prepared for the
% \DOC{} package whereas |\IndexInput| can be used for all kinds of
% macro files. See page \pageref{..Input} for more details of
% "\IndexInput". Multiple "\DocInput"s can be used with a
% number of included files which are each self-contained
% self-documenting packages---for instance, each containing
% "\maketitle".
%
% As an example, the driver file for the \DOC{} package itself is
% the following text surrounded by "%<*driver>" and "%</driver>".
% To produce the documentation you can simply run the \texttt{.dtx}
% file through \LaTeX{} in which case this code will be executed
% (loading the document class \texttt{ltxdoc}, etc.) or you can
% extract this into a separate file by using
% the \texttt{docstrip} program.
% The line numbers below are added by
% \DOC{}'s formatting.
% Note that the class \textsf{ltxdoc} has the \DOC{} package
% preloaded.
% \changes{v1.7a}{1992/03/06}{Added
% docstrip-derivable driver file as example.}
% \changes{v1.7c}{1992/04/01}{Expurgated ltugboat.sty from driver.}
% \begin{macrocode}
%<*driver>
\documentclass{ltxdoc}
\EnableCrossrefs
%\DisableCrossrefs % Say \DisableCrossrefs if index is ready
\CodelineIndex
\RecordChanges % Gather update information
%\OnlyDescription % comment out for implementation details
%\OldMakeindex % use if your MakeIndex is pre-v2.9
\setlength\hfuzz{15pt} % dont make so many
\hbadness=7000 % over and under full box warnings
\begin{document}
\DocInput{doc.dtx}
\end{document}
%</driver>
% \end{macrocode}
%
%
% \subsection{General conventions}
%
% A \TeX{} file prepared to be used with the `doc' package
% consists of `documentation parts' intermixed with `definition
% parts'.
%
% Every line of a `documentation part' starts with a percent sign
% (|%|) in column one. It may contain arbitrary \TeX{} or
% \LaTeX{} commands except that the character `|%|' cannot be
% used as a comment character.
% \SortIndex{\string^\string^A}{\string\verb\verbatimchar
% \string^\string^A\verbatimchar \encapchar usage} To allow user
% comments, the |^^A| character is defined as a comment character
% later on. Such `metacomments' may be also be included simply by
% surrounding them with "\iffalse" \ldots~"\fi".
%
% All other parts of the file are called `definition parts'. They
% contain fractions of the macros described in the `documentation
% parts'.
%
% If the file is used to define new macros (e.g.\ as a package file in
% the |\usepackage| macro), the `documentation parts' are
% bypassed at high speed and the macro definitions are pasted
% together, even if they are split into several `definition parts'.
%
% \DescribeEnv{macrocode}
% On the other hand, if the documentation of these macros is to be
% produced, the `definition parts' should be typeset verbatim. To
% achieve this, these parts are surrounded by the \textsf{macrocode}
% environment.
% More exactly: before a `definition part' there should be a line
% containing\\
% \hspace*{\MacroIndent}\verb*+% \begin{macrocode}+\\
% and after this part a line\\
% \hspace*{\MacroIndent}\verb*+% \end{macrocode}+\\
% There must be {\em exactly\/} four spaces between the |%|
% and |\end{macrocode}| --- \TeX{} is looking for this string
% and not for the macro while processing a `definition part'.
%
% Inside a `definition part' all \TeX{} commands are allowed; even the
% percent sign could be used to suppress unwanted spaces etc.
%
% \DescribeEnv{macrocode*} Instead of the \textsf{macrocode}
% environment one can also use the \textsf{macrocode$*$} environment
% which produces the same results except that spaces are printed as
% \nopagebreak\verb*+ + characters.
%
%
%
% \subsection{Describing the usage of new macros}
%
% \DescribeMacro\DescribeMacro
% When you describe a new macro you may use |\DescribeMacro| to
% indicate that at this point the usage of a specific macro is
% explained. It takes one argument which will be printed in the margin
% and also produces a special index entry. For example, I used
% |\DescribeMacro{\DescribeMacro}| to make clear that this is the
% point where the usage of |\DescribeMacro| is explained.
%
% \DescribeMacro\DescribeEnv
% An analogous macro |\DescribeEnv| should be used to indicate
% that a \LaTeX{} environment is explained. It will produce a somewhat
% different index entry. Below I used |\DescribeEnv{verbatim}|.
%
% \DescribeEnv{verbatim}
% It is often a good idea to include examples of the usage of new macros
% in the text. Because of the |%| sign in the first column of every
% row, the \textsf{verbatim} environment is slightly altered to suppress
% those
% characters.\footnote{These macros were written by Rainer
% Sch\"opf~\cite{art:verbatim}. He also
% provided a new \textsf{verbatim} environment
% which can be used inside of other macros.}
% \DescribeEnv{verbatim*}
% The \textsf{verbatim$*$} environment is changed in the same way.
% \changes{v1.7a}{1992/02/26}{Documented \cs{verb} change.}
% \DescribeMacro\verb
% The "\verb" command is re-implemented to give an error report if a
% newline appears in its argument.
% The \textsf{verbatim} and \textsf{verbatim$*$} environments set text
% in the style defined by "\MacroFont"~(\S\ref{sec:macrofont}).
%
%
%
% \subsection{Describing the definition of new macros}
%
% \DescribeEnv{macro}
% To describe the definition of a new macro we use the \textsf{macro}
% environment. It has one argument: the name of the new
% macro.\footnote{This is a change to the style design I described in
% ^^A \TUB ^^A removed in case ltugboat.sty not used
% \textsl{TUGboat\/}\ 10\#1 (Jan.~89). We finally decided
% that it would
% be better to use the macro name {\em with\/} the
% backslash as an argument.}
% This argument is also used to print the name in the margin and to
% produce an index entry.
% Actually the index entries for usage and definition are different to
% allow an easy reference.
% This environment might be nested. In this case the
% labels in the margin are placed under each other.
% \changes{v1.7a}{1992/02/26}{Note on need for some text in macro env.}
% There should be some text---even if it's just an empty
% "\mbox{}"---in this environment before "\begin{macrocode}" or the
% marginal label won't print in the right place.
%
% \DescribeMacro\MacrocodeTopsep
% \DescribeMacro\MacroTopsep
% There also exist four style parameters: |\MacrocodeTopsep| and
% |\MacroTopsep| are used to control the vertical spacing above
% and below the \textsf{macrocode} and the \textsf{macro}
% \DescribeMacro\MacroIndent
% environment, |\MacroIndent| is used to indent the lines of code
% and
% \DescribeMacro\MacroFont \label{sec:macrofont}
% |\MacroFont| holds the font and a possible size change command
% for the code lines, the "verbatim"["*"] environment and the macro
% names printed in the margin. If you want
% to change their default values in a
% class file (like \texttt{ltugboat.cls}) use the |\DocstyleParms|
% command described below. Starting with release 2.0a it can now
% be changed directly as long as the redefinition happens before
% the |\begin{document}|.
%
%
%
%
% \subsection{Formatting the margins}
%
% \DescribeMacro\PrintDescribeMacro
% \DescribeMacro\PrintDescribeEnv
% \DescribeMacro\PrintMacroName
% \DescribeMacro\PrintEnvName
% As mentioned earlier, some macros and the \textsf{macro} environment
% print their arguments in the margin. This is actually done by four
% macros which are user
% definable.\footnote{You may place the changed definitions in a
% separate package
% file or at the beginning of the documentation
% file.
% For example, if you don't like any names in the
% margin
% but want a fine index you can simply
% \texttt{\bslash let}
% these macros equal \texttt{\bslash @gobble}.
% The doc package won't redefine any existing
% definitions of these macros.}
% They are named |\PrintDescribeMacro|, |\PrintDescribeEnv|,
% |\PrintMacroName| (called by the \textsf{macro} environment) and
% |\PrintEnvName| (called by the \textsf{environment} environment).
%
%
% \subsection{Using a special escape character}
%
% \DescribeMacro\SpecialEscapechar
% If one defines complicated macros it is sometimes necessary to
% introduce a new escape character because the `|\|' has got a
% special |\catcode|. In this case one can use
% |\SpecialEscapechar| to indicate which character is actually
% used to play the r\^ole of the `|\|'. A scheme like this is
% needed because the \textsf{macrocode} environment and its counterpart
% \textsf{macrocode$*$} produce an index entry for every occurrence of a
% macro name. They would be very confused if you didn't tell them that
% you'd changed |\catcode|$\,$s. The argument to
% |\SpecialEscapechar| is a single-letter control sequence, that
% is, one has to use "\|" for example to denote that `\verb+|+'
% is used as an escape character. |\SpecialEscapechar| only
% changes the behavior of the next \textsf{macrocode} or
% \textsf{macrocode$*$} environment.
%
% The actual index entries created will all be printed with |\|
% rather than \verb+|+, but this probably reflects their usage, if not
% their definition, and anyway must be preferable to not having any
% entry at all. The entries {\em could\/} be formatted appropriately,
% but the effort is hardly worth it, and the resulting index might be
% more confusing (it would certainly be longer!).
%
%
% \subsection{Cross-referencing all macros used}
%
% \DescribeMacro\DisableCrossrefs \DescribeMacro\EnableCrossrefs As
% already mentioned, every new macro name used within a
% \textsf{macrocode} or \textsf{macrocode$*$} environment will produce
% an index entry. In this way one can easily find out where a specific
% macro is used. Since \TeX{} is considerably slower when it has to
% produce such a bulk of index entries one can turn off this feature
% by using |\DisableCrossrefs| in the driver file. To turn it on again
% just use |\EnableCrossrefs|.\footnote{Actually, \texttt{\bslash
% EnableCrossrefs} changes things more drastically; any following
% \texttt{\bslash DisableCrossrefs} which might be present in the
% source will be ignored.}
%
%
% \DescribeMacro\DoNotIndex
% But also finer control is provided. The |\DoNotIndex| macro
% takes a list of macro names separated by commas. Those names won't
% show up in the index. You might use several |\DoNotIndex|
% commands: their lists will be concatenated. In this article I used
% |\DoNotIndex| for
% all macros which are already defined in \LaTeX.
%
% All three above declarations are local to the current group.
%
% Production (or not) of the index (via the "\makeindex" commend) is
% controlled by using or omitting the following declarations in the
% driver file preamble; if neither is used, no index is produced.
% \DescribeMacro\PageIndex Using "\PageIndex" makes all index
% entries refer to their page number; with
% \DescribeMacro\CodelineIndex "\CodelineIndex", index entries
% produced by "\DescribeMacro" and "\DescribeEnv" refer to page number
% but those produced by the \textsf{macro} environment refer to the
% code lines, which will be numbered automatically.\footnote{The line
% number is actually that of the first line of the first
% \textsf{macrocode} environment in the \textsf{macro} environment.}
% \DescribeMacro\theCodelineNo
% The style of this numbering can be controlled by defining the macro
% "\theCodelineNo". Its default definition is to use scriptsize
% arabic numerals; a user-supplied definition won't be overwritten.
%
% \DescribeMacro\CodelineNumbered
% When you don't wish to get an index but want your code lines
% numbered use "\CodelineNumbered" instead of "\CodelineIndex". This
% prevents the generation of an unnecessary ".idx" file.
%
%
% \subsection{Producing the actual index entries}
%
% Several of the aforementioned macros will produce some sort of index
% entries. These entries have to be sorted by an external
% program---the current implementation assumes that the
% \textsf{makeindex} program by Chen~\cite{art:Chen} is used.
%
% But this isn't built in: one has only to redefine some of the
% following macros to be able to use any other index program. All
% macros which are installation
% dependent are defined in such a way that they won't overwrite a
% previous definition. Therefore it is safe to put the changed
% versions in a package file which might be read in before the doc
% package.
%
% To allow the user to change the specific characters recognized by
% his or her index program all characters which have special meaning
% in the \textsf{makeindex} program are given symbolic
% names.\footnote{I don't know if there exists a program which needs
% more command characters, but I hope not.}
% However, all characters used should be of |\catcode| other than
% `letter' (11).
%
% \DescribeMacro{\actualchar}
% The |\actualchar| is used to separate the `key' and the actual
% index entry.
% \DescribeMacro{\quotechar}
% The |\quotechar| is used before a special index program
% character to suppress its special meaning.
% \DescribeMacro{\encapchar}
% The |\encapchar| separates the indexing information from a
% letter string which \textsf{makeindex} uses as a \TeX{} command to
% format the page number associated with a special entry. It is used
% in this package to apply the |\main| and the |\usage|
% commands.
% \DescribeMacro{\levelchar}
% Additionally |\levelchar| is used to separate `item',
% `subitem' and `subsubitem' entries.
%
% It is a good idea to stick to these symbolic names even if you know
% which index program is used. In this way your files will be
% portable.
%
% \DescribeMacro\SpecialMainIndex
% \DescribeMacro\SpecialMainEnvIndex
% To produce a main index entry for a macro the
% |\SpecialMainIndex| macro\footnote{This macro is called by the
% \textsf{macro} environment.} may be used. It is called `special'
% because it has to print its argument verbatim.
% A similar macro, called |\SpecialMainEnvIndex| is used for indexing
% the main definition point of an
% environment.\footnote{This macro is called by the
% \textsf{environment} environment.}
% \DescribeMacro\SpecialIndex
% If you want a normal index entry for a macro name
% |\SpecialIndex| might be used.\footnote{This macro is called
% within the \textsf{macrocode} environment when encountering a macro
% name.}
% \DescribeMacro\SpecialUsageIndex
% \DescribeMacro\SpecialEnvIndex
% To index the usage of a macro or an environment
% |\SpecialUsageIndex| and |\SpecialEnvIndex| may be used.
% \DescribeMacro\SortIndex
% Additionally a |\SortIndex| command is provided. It takes two
% arguments---the sort key and the actual index entry.
%
% All these macros are normally used by other macros; you will need
% them only in an emergency.
%
% \DescribeMacro\verbatimchar
% But there is one characteristic worth mentioning: all macro names in
% the index are typeset with the |\verb*| command. Therefore one
% special character is needed to act as a delimiter for this command.
% To allow a change in this respect, again this character is
% referenced indirectly, by the macro |\verbatimchar|. It expands
% by default to \verb?+? but if your code lines contain macros with
% `\texttt{+}' characters in their names (e.g.\ when you use \verb?\+?)
% you will end up with an index entry containing \verb?\verb+\++?
% which will be typeset as `\verb+\++' and not as `\verb?\+?'. In this
% case you should redefine |\verbatimchar| globally or locally to
% overcome this problem.
%
% \DescribeMacro\*
% We also provide a |\*| macro. This is intended to be used for
% index entries like
% \begin{quote}
% index entries \\
% \hspace*{30pt} Special macros for \*
% \end{quote}
% Such an entry might be produced with the line:
%\begin{verbatim}
% \index{index entries\levelchar Special macros for \*}
%\end{verbatim}
%
% \DescribeMacro\OldMakeindex
% Versions of \textsf{makeindex} prior to 2.9 had some bugs affecting
% \DOC{}. One of these,
% pertaining to the "%" character doesn't have a work-around
% appropriate for versions with and without the
% bug.\label{makeindex:version} If
% you have an old version, invoke "\OldMakeindex" in a
% package file or the driver file to prevent problems with index entries
% such as "\%", although you'll probably normally want to turn off
% indexing of "\%" anyway. Try to get an up-to-date \textsf{makeindex}
% from one of the \TeX{} repositories.
%
%
% \subsection{Setting the index entries}
%
% \changes{v1.7a}{1992/03/11}{Usage note on gind.ist.} After the first
% formatting pass through the \texttt{.dtx} file you need to sort the
% index entries written to the \texttt{.idx} file using
% \textsf{makeindex} or your favourite alternative. You need a
% suitable style file for \textsf{makeindex} (specified by the
% \texttt{-s} switch). A suitable one is supplied with \DOC{},
% called \texttt{gind.ist}.
%
% \DescribeMacro\PrintIndex
% To read in and print the sorted index, just put the
% |\PrintIndex| command as the last (commented-out, and thus
% executed during the documentation pass through the file) command
% in your package file. Precede it by any bibliography commands
% necessary for your citations.
% Alternatively, it may be more convenient to put all such calls
% amongt the arguments of the |\StopEventually| macro, in
% which case a |\Finale| command should appear at the end of
% your file.
%
% \DescribeEnv{theindex}
% Contrary to standard \LaTeX, the index is typeset in three columns
% by default. This is controlled by the \LaTeX{} counter
% `\textsf{IndexColumns}' and can therefore be changed with a
% |\setcounter| declaration. Additionally one doesn't want to
% start a new page unnecessarily. Therefore the \textsf{theindex}
% environment is redefined.
% \DescribeMacro\IndexMin
% When the \textsf{theindex} environment starts it will measure how much
% space is left on the current page. If this is more than
% |\IndexMin| then the index will start on this page. Otherwise
% |\newpage| is called.
%
% Then a short introduction about the meaning of several index entries
% is typeset (still in onecolumn mode). Afterwards the actual index
% entries follow in multi-column mode.
% \DescribeMacro\IndexPrologue
% You can change this prologue with the help of the
% |\IndexPrologue| macro. Actually the section heading is also
% produced in this way, so you'd better write something like:
% \begin{verbatim}
% \IndexPrologue{\section*{Index} The index entries underlined ...}
%\end{verbatim}
% When the \textsf{theindex} environment is finished the last page will
% be reformatted to produce balanced columns. This improves the layout
% and allows the next article to start on the same page.
% \DescribeMacro\IndexParms
% Formatting of the index columns (values for |\columnssep|
% etc.)\ is controlled by the |\IndexParms| macro. It assigns the
% following values:
% \SpecialUsageIndex{\parindent}\SpecialUsageIndex{\columnsep}^^A
% \SpecialUsageIndex{\parskip}\SpecialUsageIndex{\rightskip}^^A
% \SpecialUsageIndex{\mathsurround}\SpecialUsageIndex{\parfillskip}
% \begin{center}
% \begin{tabular}{l@{\,=\,}ll@{\,=\,}l}
% |\parindent| & \IndexParms \the\parindent &
% |\columnsep| & \IndexParms \the\columnsep \\
% |\parskip| & \IndexParms \the\parskip &
% |\rightskip| & \IndexParms
% \expandafter\dimenvalue\the\rightskip \\
% |\mathsurround| & \IndexParms \the\mathsurround &
% |\parfillskip| & \IndexParms
% \expandafter\dimenvalue\the\parfillskip
% \end{tabular}
% \end{center}
% \DescribeMacro{\@idxitem}
% Additionally it defines |\@idxitem| (which will be used when an
% |\item| command is encountered) and selects |\small| size.
% If you want to change any of these values you have to define them
% all.
%
% \DescribeMacro\main
% \DescribeMacro\usage
% The page numbers for main index entries are encapsulated by the
% |\main| macro (underlining its argument) and the numbers
% denoting the description are encapsulated by the |\usage| macro
% (which produces {\em italics}). As usual these commands are user
% definable.
%
%
% \subsection{Changing the default values of style parameters}
%
% \DescribeMacro\DocstyleParms If you want to overwrite some default
% settings made by the \DOC{} package, you can either put your
% declarations in the driver file (that is after \texttt{doc.sty} is
% read in) or use a separate package file for doing this work. In the
% latter case you can define the macro |\DocstyleParms| to contain all
% assignments. This indirect approach is necessary if your package file
% might be read before the \texttt{doc.sty}, when some of the
% registers are not allocated. Its default definition is null.
%
% The doc package currently assigns values to the following
% registers:
% \SpecialUsageIndex{\IndexMin}\SpecialUsageIndex{\MacrocodeTopsep}^^A
% \SpecialUsageIndex{\MacroTopsep}^^A
% \SpecialUsageIndex{\MacroIndent}\SpecialUsageIndex{\marginparpush}^^A
% \SpecialUsageIndex{\marginparwidth}\SpecialUsageIndex{\tolerance}
% \begin{center}
% \begin{tabular}{l@{\,=\,}ll@{\,=\,}l}
% |\IndexMin| & \the\IndexMin &
% |\MacroTopsep| & \the\MacroTopsep \\
% |\marginparwidth|& \the\marginparwidth &
% |\MacroIndent| & \the\MacroIndent \\
% |\marginparpush| & \the\marginparpush &
% |\MacrocodeTopsep| & \the\MacrocodeTopsep \\
% |\tolerance| & \the\tolerance
% \end{tabular}
% \end{center}
%
%
% \subsection{Short input of verbatim text pieces}
%
% \DescribeMacro\MakeShortVerb
% \DescribeMacro{\MakeShortVerb*} \DescribeMacro\DeleteShortVerb It is
% awkward to have to type, say, "\verb|"\ldots"|" continually when
% quoting
% verbatim bits (like macro names) in the text, so an abbreviation
% mechanism is provided. Pick a character \meta{c}---one which
% normally has catcode `other' unless you have very good reason not
% to---which you don't envisage using in the text, or not using often.
% (I like |"|, but you may prefer "|" if you have |"| active to do
% umlauts, for instance.) Then if you say
% "\MakeShortVerb{\"\meta{c}"}" you can subsequently use
% \meta{c}\meta{text}\meta{c} as the equivalent of
% "\verb"\meta{c}\meta{text}\meta{c}; analogously, the "*"-form
% "\MakeShortVerb*{\"\meta{c}"}" gives you the equivalent of
% "\verb*"\meta{c}\meta{text}\meta{c}. Use
% "\DeleteShortVerb{\"\meta{c}"}" if you subsequently want \meta{c} to
% revert to its previous meaning---you can always turn it on again
% after the unusual section. The `short verb' commands make global
% changes. The abbreviated "\verb" may not appear in the argument of
% another command just like "\verb". However the `short verb'
% character may be used freely in the \textsf{verbatim} and
% \textsf{macrocode} environments without ill effect.
% "\DeleteShortVerb" is silently ignored if its argument does not
% currently represent a short verb character. Both commands type a
% message to tell you the meaning of the character is being changed.
%
% Please remember that the command "\verb" cannot be used in arguments
% of other commands. Therefore abbreviation characters for "\verb"
% cannot be used there either.
%
% This feature is also available as a sole package, \texttt{shortvrb}.
%
%
% \subsection{Additional bells and whistles}
%
% We provide macros for logos such as \Web, \AmSTeX, \BibTeX,
% \SliTeX{} and \PlainTeX. Just type |\Web|, |\AmSTeX|,
% |\BibTeX|, |\SliTeX| or |\PlainTeX|, respectively.
% \LaTeX{} and \TeX{} are already defined in the \LaTeX{} format.
%
% \DescribeMacro\meta
% Another useful macro is |\meta| which has one argument and
% produces something like \meta{dimen parameter}.
%
% \DescribeMacro\OnlyDescription
% \DescribeMacro\StopEventually
% You can use the |\OnlyDescription| declaration in the driver
% file to suppress the last part of your document (which presumably
% exhibits the code). To make this work
% you have to place the command |\StopEventually| at a suitable
% point in your file. This macro has one argument in which you put
% all information you want to see printed if your document ends at
% this point (for example a bibliography which is normally printed at
% the very end). When the |\OnlyDescription| declaration is
% missing the |\StopEventually|
% \DescribeMacro\Finale
% macro saves its argument in a macro called |\Finale| which can
% afterwards be used to get things back (usually at the very end).
% Such a scheme makes changes in two places unnecessary.
%
% Thus you can use this feature to produce a local guide for the
% \TeX{} users which describes only the usage of macros (most of them
% won't be interested in your definitions anyway). For the same
% reason the |\maketitle| \DescribeMacro\maketitle command is slightly
% changed to allow multiple titles in one document. So you can make
% one driver file reading in several articles at once.
% \DescribeMacro{\ps@titlepage} To avoid an unwanted
% \textsf{pagestyle} on the title page the |\maketitle| command issues
% a |\thispagestyle{titlepage}| declaration which produces a
% \textsf{plain} page if the \textsf{titlepage} page style is
% undefined. This allows class files like \textsf{ltugboat.cls} to
% define their own page styles for title pages.
%
% \DescribeMacro\AlsoImplementation
% Typesetting the whole document is the default. However, this default
% can also be explicitly selected using the declaration
% |\AlsoImplementation|. This overwrites any previous
% |\OnlyDescription| declaration. The \LaTeXe{} distribution, for
% example, is documented using the \texttt{ltxdoc} class which allows
% for a configuration file \texttt{ltxdoc.cfg}. In such a file one
% could then add the statement
% \begin{quote}
% |\AtBeginDocument{\AlsoImplementation}|
% \end{quote}
% to make sure that all documents will show the code part.
%
% \DescribeMacro\IndexInput \label{..Input} Last but not least I
% defined an |\IndexInput| macro which takes a file name as an
% argument and produces a verbatim listing of the file, indexing every
% command as it goes along. This might be handy, if you want to learn
% something about macros without enough documentation. I used this
% feature to cross-reference \texttt{latex.tex} (these days
% called \texttt{latex.ltx}) getting a verbatim
% copy with about 15 pages index.\footnote{It took quite a long time
% and the resulting \texttt{.idx} file was longer than the
% \texttt{.dvi} file. Actually too long to be handled by the
% \textsf{makeindex} program directly (on our MicroVAX) but the final
% result was worth the trouble.}
%
% \changes{v2.1d}{2006/02/02}{Corrected description of \cs{changes}
% macro.}
% \DescribeMacro\changes
% To maintain a change history within the file, the |\changes|
% command may be placed amongt the description part of the changed
% code. It takes three arguments, thus:
% \begin{quote}
% |\changes{|\meta{version}|}{|\meta{date}|}{|^^A
% \meta{text}|}|
% \end{quote}
% The changes may be used to produce an auxiliary file (\LaTeX's
% |\glossary| mechanism is used for this) which may be printed
% after suitable formatting. The |\changes| macro generates the
% printed entry in such a change history; because old
% versions\footnote{Before 2.6.} of the \textsf{makeindex}
% program limit such fields to 64 characters, care should be taken
% not to exceed this limit when describing the change. The actual
% entry consists of the \meta{version}, the |\actualchar|, the current
% macro name, a colon, the |\levelchar|, and, finally, the \meta{text}.
% The result is a glossaryentry for the \meta{version}, with the name of
% the current macro as subitem. Outside the |macro| environment, the
% text |\generalname| is used instead of the macro name. When
% referring to macros in change descriptions it is conventional to use
% |\cs{|\meta{macroname}|}| rather than attempting to format it properly
% and using up valuable characters in the entry with old \textsf{makeindex}
% versions.
%
% \changes{v1.7a}{1992/02/26}{Description of \cs{RecordChanges} etc.
% added
% to interface section.} \DescribeMacro\RecordChanges To cause the
% change information to be written out, include "\RecordChanges" in
% the driver file. \DescribeMacro\PrintChanges To read in and print
% the sorted change history (in two columns), just put the
% |\PrintChanges| command as the last (commented-out, and thus
% executed during the documentation pass through the file) command in
% your package file. Alternatively, this command may form one of the
% arguments of the |\StopEventually| command, although a change
% history is probably {\em not\/} required if only the description is
% being printed. The command assumes that \textsf{makeindex} or some
% other program has processed the \texttt{.glo} file to generate a
% sorted \texttt{.gls} file. You need a special \textsf{makeindex}
% style file; a suitable one is supplied with \DOC{}, called
% \texttt{gglo.ist}. \DescribeMacro\GlossaryMin
% \DescribeMacro\GlossaryPrologue \DescribeMacro\GlossaryParms The
% "\GlossaryMin", "\GlossaryPrologue" and "\GlossaryParms" macros are
% analogous to the "\Index"\ldots\ versions. (The \LaTeX{} `glossary'
% mechanism is used for the change entries.)
%
% \label{sec:checksum}
% \DescribeMacro\CharacterTable
% \DescribeMacro\CheckSum
% To overcome some of the problems of sending files over the networks
% we developed two macros which should detect corrupted files. If one
% places the lines
% \begin{flushleft}
% \small\ttfamily ^^A \ttfamily to get the blanks between "..."s
% ^^A right
%"%%\CharacterTable"\\
%"%% {Upper-case "
%"\A\B\C\D\E\F\G\H\I\J\K\L\M\N\O\P\Q\R\S\T\U\V\W\X\Y\Z"\\
%"%% Lower-case "
%"\a\b\c\d\e\f\g\h\i\j\k\l\m\n\o\p\q\r\s\t\u\v\w\x\y\z"\\
%"%% Digits \0\1\2\3\4\5\6\7\8\9"\\
%"%% Exclamation \! Double quote "\verb=\"=
%" Hash (number) \#"\\
%"%% Dollar \$ Percent \% Ampersand \&"\\
%"%% Acute accent \' Left paren \( Right paren \)"\\
%"%% Asterisk \* Plus \+ Comma \,"\\
%"%% Minus \- Point \. Solidus \/"\\
%"%% Colon \: Semicolon \; Less than \<"\\
%"%% Equals \= Greater than \> Question mark \?"\\
%"%% Commercial at \@ Left bracket \[ Backslash \\"\\
%"%% Right bracket \] Circumflex \^ Underscore \_"\\
%"%% Grave accent \` Left brace \{ Vertical bar \|"\\
%"%% Right brace \} Tilde \~}"\\
%"%%"
%\end{flushleft}
% at the beginning of the file then character translation failures
% will be detected, provided of course, that the used \DOC{}
% package has a correct default table. The percent
% signs\footnote{There are two percent signs in each line. This has
% the effect that these lines are not removed by the
% \texttt{docstrip.tex} program.} at the beginning of the lines should
% be typed in, since only the \DOC{} package should look at this
% command.
%
%
% Another problem of mailing files is possible truncation. To detect
% these sort of errors we provide a |\CheckSum| macro. The check-sum
% of a file is simply the number of backslashes in the code, i.e.\ all
% lines between the \textsf{macrocode} environments. But don't be
% afraid: you don't have count the code-lines yourself; this is done
% by the \DOC{} package for you. You simply have add
% \begin{quote}
% |% \CheckSum{0}|
% \end{quote}
% near the beginning of the file and
% use
% the |\StopEventually| (which starts looking for backslashes) and the
% |\Finale| command. The latter will inform you either that your file
% has no check-sum (telling you the right number) or that your number
% is incorrect if you put in anything other than zero but guessed wrong (this time
% telling you both the correct and the
% incorrect one). Then you go to the top of your file again and change the
% line to the right number, i.e.
% line
% \begin{quote}
% |% \CheckSum{|\meta{number}|}|
% \end{quote}
% and that's all.
%
% While |\CharacterTable| and |\CheckSum| have been important features
% in the early days of the public internet when \DOC{} was written as
% the mail gateways back then were rather unreliable and often mangled
% files they are these days more a nuisance than any help. They are
% therefore now fully optional and no longer recommended for use with new files.
%
%
% \DescribeMacro\bslash
% From time to time, it is necessary to print a |\| without
% being able to use the |\verb| command because the
% |\catcode|$\,$s of the symbols are already firmly
% established. In this instance we can use the command
% |\bslash| presupposing, of course, that the actual font in
% use at this point contains a `backslash' as a symbol. Note that
% this definition of |\bslash| is expandable; it inserts a
% $"\"_{12}$. This means that you have to |\protect|
% it if it is used in `moving arguments'.
%
% \DescribeMacro\MakePrivateLetters
% \changes{v1.7a}{1992/02/26}{Documented \cs{MakePrivateLetters} in
% interface section}^^A
% If your macros "\catcode" anything other than "@" to `letter', you
% should redefine "\MakePrivateLetters" so that it also makes the
% relevant characters `letters' for the benefit of the indexing. The
% default definition is just "\makeatletter".
%
% \DescribeMacro\DontCheckModules \DescribeMacro\CheckModules
% \DescribeMacro\Module \DescribeMacro\AltMacroFont The `module'
% directives of the \textsf{docstrip} system \cite{art:docstrip} are
% normally recognised and invoke special formatting. This can be
% turned on and off in the \texttt{.dtx} file or the driver file using
% "\CheckModules" and "\DontCheckModules". If checking for module
% directives is on (the default) then code in the scope of the
% directives is set as determined by the hook "\AltMacroFont", which
% gives {\small\ttfamily\itshape small italic type\-writer\/} by
% default in the New Font Selection Scheme but just ordinary
% {\small\ttfamily small type\-writer} in the old one, where a font
% such as italic typewriter can't be used portably (plug for NFSS);
% you will need to override this if you don't have the italic
% typewriter font available. Code is in such a scope if it's on a
% line beginning with "%<" or is between lines starting with
% "%<*"\meta{name list}">" and "%</"\meta{name list}">". The
% directive is formatted by the macro "\Module" whose single argument
% is the text of the directive between, but not including, the angle
% brackets; this macro may be re-defined in the driver or package file
% and by default produces results like \Module{+foo\string|bar} with no
% following space.
%
% \DescribeMacro{StandardModuleDepth} Sometimes (as in this file) the
% whole code is surrounded by modules to produce several files from a
% single source. In this case it is clearly not appropriate to format
% all code lines in a special "\AltMacroFont". For this reason a
% counter "StandardModuleDepth" is provided which defines the level of
% module nesting which is still supposed to be formatted in
% "\MacroFont" rather then "\AltMacroFont". The default setting is
% "0", for this documentation it was set to
%\begin{verbatim}
% \setcounter{StandardModuleDepth}{1}
%\end{verbatim}
% at the beginning of the file.
%
%
% \subsection{Basic usage summary}
% \changes{v1.7a}{1992/03/11}{Added basic usage summary to spell
% it out.}
%
% To sum up, the basic structure of a \texttt{.dtx} file without any
% refinements is like this:
% \begin{verse}\small
% "% "\meta{waffle}\ldots\\
% \quad\ldots \\
% "% \DescribeMacro{\fred}"\\
% "% "\meta{description of fred's use}\\
% \quad\ldots\\
% "% \StopEventually{"\meta{finale code}"}"\\
% \quad\ldots\\
% "% \begin{macro}{\fred}"\\
% "% "\meta{commentary on macro fred}\\
% \verb*+% \begin{macrocode}+\\
% \meta{code for macro fred}\\
% \verb*+% \end{macrocode}+\\
% "% \end{macro}"\\
% \quad\ldots\\
% "% \Finale \PrintIndex \PrintChanges"
% \end{verse}
% For examples of the use of most---if not all---of the features
% described above consult the \texttt{doc.dtx} source itself.
%
% \subsection{Acknowledgements}
%
% I would like to thank all folks at Mainz and at the Royal Military
% College of Science for their help in this project. Especially Brian
% and Rainer who pushed everything with their suggestions, bug fixes,
% etc.
%
% A big thank you to David Love who brought the documentation
% up-to-date again, after I neglected this file for more than two
% years. This was most certainly a tough job as many features added to
% \texttt{doc.dtx} after its publication in \textsl{TUGboat\/} have
% been never properly described. Beside this splendid work he kindly
% provided additional code (like ``docstrip'' module formatting) which
% I think every \textsf{doc.dtx} user will be grateful for.
%
%
% \StopEventually{
% \begin{thebibliography}{1}
% \bibitem{book:Buerger} \textsc{G. A. B\"urger}.
% \newblock Wunderbare Reisen zu Wasser und zu Lande, Feldz\"uge
% und lustige Abenteuer des Freyherrn v.\ M\"unchhausen.
% \newblock London, 1786 \& 1788.
% \bibitem{art:Knuthliterat} \textsc{D. E. Knuth}.
% \newblock Literate Programming.
% \newblock Computer Journal, Vol.~27, \textit{pp}.~97--111,
% May 1984.
% \bibitem{book:KnuthA} \textsc{D. E. Knuth}.
% \newblock Computers \& Typesetting (The \TeX book).
% \newblock Addison-Wesley, Vol. A, 1986.
% \bibitem{art:Chen} \textsc{L. Lamport}.
% \newblock MakeIndex: An Index Processor for \LaTeX.
% \newblock 17 February 1987.
% \newblock (Taken from the file \texttt{makeindex.tex} provided
% with
% the program source code.)
% \bibitem{art:doc} \textsc{Frank Mittelbach}.
% \newblock The \DOC{}-option.
% \newblock \textsl{TUGboat}, Vol.~10(2), \textit{pp}.~245--273,
% July 1989.
% \bibitem{art:docstrip} \textsc{Frank Mittelbach, Denys Duchier and
% Johannes Braams}.
% \newblock \texttt{docstrip.dtx} (to appear).
% \newblock The file is part of the DOC package.
% \bibitem{book:Raspe} \textsc{R. E. Raspe} (*1737, \dag 1797).
% \newblock Baron M\"unchhausens narrative of his marvellous
% travels and campaigns in Russia.
% \newblock Oxford, 1785.
% \bibitem{art:verbatim} \textsc{Rainer Sch\"opf}.
% \newblock A New Implementation of \LaTeX's \texttt{verbatim} and
% \texttt{verbatim*} Environments.
% \newblock File \texttt{verbatim.doc}, version 1.4i.
% \end{thebibliography}
%
% \ifmulticols
% \addtocontents{toc}{\protect\end{multicols}}
% \fi
%
% } ^^A end \StopEventually
%
%
% \section{The Description of Macros}
%
% Most of the following code is destined for \texttt{doc.sty} after
% processing with \texttt{docstrip} to include the module
% \textbf{style} indicated here. (All code in this file not
% appropriate to \texttt{doc.sty} has to be included explicitly by
% docstrip so that this \texttt{.dtx} file can be used as directly as
% a package file rather than the stripped version.) The usual font
% change for the conditionally-included lines between the
% \Module{*style} and \Module{/style} directives is suppressed since
% only the lines with an explicit directive are special in this file.
% \begin{macrocode}
%<*package>
% \end{macrocode}
% Under \LaTeXe{} the test to avoid reading
% \DOC{} in twice is normally unnecessary. It was kept to only to
% stay compatible with \LaTeX209 styles that |\input| \DOC{}
% directly.
% \changes{v1.5i}{1989/06/07}{Avoid reading the file twice.}
% \begin{macrocode}
\@ifundefined{macro@cnt}{}{\endinput}
% \end{macrocode}
%
% \DescribeMacro\fileversion
% \DescribeMacro\filedate
% \DescribeMacro\docdate
% As you can see I used macros like |\fileversion| to denote the
% version number and the date. They are defined at the very beginning
% of the package file (without a surrounding \textsf{macrocode}
% environment), so I don't have to search for this place here when I
% change the version number. You can see their actual outcome in a
% footnote to the title.
%
%
% The first thing that we do next is to get ourselves a new comment
% sign. Because all sensible signs are already occupied, we will
% choose one that can only be entered indirectly:
% {\DoNotIndex{\^}^^A avoid misinterpretation !!!!! VERIFY
% \begin{macrocode}
\catcode`\^^A=14
% \end{macrocode}
% We repeat this statement at the beginning of the document in case
% the \texttt{inputenc} package is used disabling it again.
% \changes{v2.0b}{1998/05/19}{Init docs private comment char at begin
% of document again (pr2581)}
% \begin{macrocode}
\AtBeginDocument{\catcode`\^^A=14\relax}
% \end{macrocode}
% \SortIndex{\string^\string^A}{\string\verb\verbatimchar
% \string^\string^A\verbatimchar
% \encapchar main}
% }
%
%
% \subsection{Options supported by \DOC{}}
%
% Not options available at the moment
%
% \begin{macrocode}
% \end{macrocode}
%
%
% \subsection{Macros surrounding the `definition parts'}
%
% \begin{environment}{macrocode}
% Parts of the macro definition will be surrounded by the
% environment \textsf{macrocode}. Put more precisely, they will be
% enclosed by a macro whose argument (the text to be set
% `verbatim') is terminated by the string
% \verb*+% \end{macrocode}+. Carefully note the number of spaces.
% |\macrocode| is defined completely analogously to
% |\verbatim|, but because a few small changes were carried
% out, almost all internal macros have got new names. We start by
% calling the macro |\macro@code|, the macro which bears the
% brunt of most of the work, such as |\catcode| reassignments,
% etc.
% \changes{v1.5r}{1989/11/04}{Support for code line no. (Undoc)}
% \begin{macrocode}
\def\macrocode{\macro@code
% \end{macrocode}
% Then we take care that all spaces have the same width, and that
% they are not discarded.
% \begin{macrocode}
\frenchspacing \@vobeyspaces
% \end{macrocode}
% Before closing, we need to call |\xmacro@code|. It is this
% macro that expects an argument which is terminated by the above
% string. This way it is possible to keep the |\catcode|
% changes local.
% \changes{v1.5r}{1989/11/04}{Support for code line no. (Undoc)}
% \changes{v1.5t}{1989/11/07}{Common code moved to \cs{macro@code}.}
% \begin{macrocode}
\xmacro@code}
% \end{macrocode}
% \end{environment}
%
%
% \begin{macro}{\macro@code}
% We will now begin with the macro that does the actual work:
% \begin{macrocode}
\def\macro@code{%
% \end{macrocode}
% In theory it should consist of a \textsf{trivlist} environment, but
% the empty space before and after the environment should not be
% too large.
% \begin{macrocode}
\topsep \MacrocodeTopsep
% \end{macrocode}
% The next parameter we set is |\@beginparpenalty|, in order
% to prevent a page break before such an environment.
% \begin{macrocode}
\@beginparpenalty \predisplaypenalty
% \end{macrocode}
% We then start a |\trivlist|, set |\parskip| back to
% zero and start an empty |\item|.
% \changes{v1.9b}{1993/12/03}{Forcing any label from macro env.}
% \begin{macrocode}
\if@inlabel\leavevmode\fi
\trivlist \parskip \z@ \item[]%
% \end{macrocode}
% The \cs{item} command sets the \cs{@labels} box but that box is
% never typeset (as \cs{everypar} that normally does this gets
% redefined later). That is normally not an issue, but produces a
% problem when typesetting in mixed directions, (e.g., in
% Japanese), so we explicitly clear it for that use case.
% \changes{v2.1m}{2020/06/15}{Void \cs{@labels} for vertical
% typesetting (gh/344)}
% \begin{macrocode}
\global\setbox\@labels\box\voidb@x
% \end{macrocode}
% Additionally, everything should be set in \texttt{typewriter} font.
% Some people might prefer it somewhat differently; because of this
% the font choice is
% macro-driven.\footnote{The font change has to be placed
% {\em after\/}
% the \texttt{\bslash item}. Otherwise a change to
% \texttt{\bslash baselineskip} will affect the
% paragraph above.}
% \begin{macrocode}
\macro@font
% \end{macrocode}
% Because |\item| sets various parameters, we have found it
% necessary to alter some of these retrospectively.
% \begin{macrocode}
\leftskip\@totalleftmargin \advance\leftskip\MacroIndent
\rightskip\z@ \parindent\z@ \parfillskip\@flushglue
% \end{macrocode}
% The next line consists of the \LaTeX{} definition of |\par|
% used in |\verbatim| and should result in blank lines being
% shown as blank lines.
% \changes{v1.5l}{1989/09/10}{Code line numbers supported.}
% \changes{v1.5t}{1989/11/07}{Call \cs{leavevmode} to get \cs{everypar}
% on blank lines.}
% \changes{v1.7c}{1992/03/24}{Added \cs{interlinepenalty} to
% \cs{par} from
% verbatim.sty}
% \begin{macrocode}
\blank@linefalse \def\par{\ifblank@line
\leavevmode\fi
\blank@linetrue\@@par
\penalty\interlinepenalty}
% \end{macrocode}
% What use is this definition of |\par|\,? We use the macro
% |\obeylines| of \cite{book:KnuthA} which changes all |^^M|
% to |\par| so that each can control its own indentation.
% Next we must also ensure that all special signs are normalized;
% that is, they must be given |\catcode| $12$.
% \changes{v1.8b}{1993/09/21}{Changed to conform to new LaTeX verbatim,
% which handles more ligatures.}
% \begin{macrocode}
\obeylines
\let\do\do@noligs \verbatim@nolig@list
\let\do\@makeother \dospecials
% \end{macrocode}
% \changes{v1.5t}{1989/11/07}{Common code added.}
% \changes{v1.5w}{1990/02/05}{Skip of \cs{@totalleftmargin} added.} If
% indexing by code lines is switched on the line number is incremented
% and set appropriately. We also check whether the start of the next
% line indicates a \texttt{docstrip} module directive and process it
% appropriately if so using "\check@module".
% \begin{macrocode}
\global\@newlistfalse
\global\@minipagefalse
\ifcodeline@index
\everypar{\global\advance\c@CodelineNo\@ne
\llap{\theCodelineNo\ \hskip\@totalleftmargin}%
\check@module}%
\else \everypar{\check@module}%
\fi
% \end{macrocode}
% We also initialize the cross-referencing feature by calling
% |\init@crossref|. This will start the scanning mechanism
% when encountering an escape character.
% \begin{macrocode}
\init@crossref}
% \end{macrocode}
% \end{macro}
%
%
% \begin{macro}{\ifblank@line}
% \begin{macro}{\blank@linetrue}
% \begin{macro}{\blank@linefalse}
% |\ifblank@line| is the switch used in the definition above.
% In the original \textsf{verbatim} environment the |\if@tempswa|
% switch is used. This is dangerous because its value may change
% while processing lines in the \textsf{macrocode} environment.
% \begin{macrocode}
\newif\ifblank@line
% \end{macrocode}
% \end{macro}
% \end{macro}
% \end{macro}
%
% \begin{macro}{\endmacrocode}
% Because we have begun a \textsf{trivlist} environment in the
% \textsf{macrocode} environment, we must also end it. We must
% also act on the value of the "pm@module" flag (see below) and
% empty "\everypar".
% \changes{v1.5r}{1989/11/04}{Support for code line no. (Undoc)}
% \begin{macrocode}
\def\endmacrocode{%
\ifpm@module \endgroup \pm@modulefalse \fi
\everypar{}%
\global\@inlabelfalse
\endtrivlist
% \end{macrocode}
% Additionally |\close@crossref| is used to do anything needed
% to end the cross-referencing mechanism.
% \begin{macrocode}
\close@crossref}
% \end{macrocode}
% \end{macro}
%
%
% \begin{macro}{\MacroFont}
% Here is the default definition for the |\MacroFont| macro.
% With the new math font handling in NFSS2 it isn't any longer
% correct to suppress the math font setup since this is now handled
% differently. But to keep the font change fast we use only a
% single |\selectfont| (in |\small|) and do the rest by hand.
% \changes{v1.5x}{1990/02/17}{\cs{math@fontsfalse} added for NFSS.}
% \changes{v1.7a}{1992/03/13}{Added \cs{reset@font} for NFSS.}
% \changes{v1.8c}{1993/10/25}{NFSS standard}
% \changes{v1.9t}{1995/05/26}{Removed \cs{math@fontsfalse} (different
% math setup /pr1622}
% \begin{macrocode}
\@ifundefined{MacroFont}{%
\if@compatibility
% \end{macrocode}
% Despite the above statement we will call |\small| first if
% somebody is using a \LaTeX2.09 document with doc. I wouldn't have
% bothered since doc-sources should be up-to-date but since the
% request came from someone called David Carlisle \ldots :-)
% \changes{v1.9y}{1996/01/26}{Support compat mode}
% \changes{v2.1l}{2019/12/16}{Use \cs{shapedefault} not
% \cs{updefault} for extended NFSS}
% \begin{macrocode}
\def\MacroFont{\small
\usefont\encodingdefault
\ttdefault
\mddefault
\shapedefault
}%
\else
\def\MacroFont{\fontencoding\encodingdefault
\fontfamily\ttdefault
\fontseries\mddefault
\fontshape\shapedefault
\small}%
\fi
}{}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\AltMacroFont}
% \begin{macro}{\macro@font}
% \changes{v1.7a}{1992/03/12}{Added to support distinction of modules.}
% \changes{v1.7c}{1992/03/26}{Altered font change for OFSS.}
% \changes{v1.7m}{1992/10/11}{Use sltt as default.}
% \changes{v1.8c}{1993/10/25}{NFSS standard}
% \changes{v1.9t}{1995/05/26}{Removed \cs{math@fontsfalse} (different
% math setup /pr1622}
% Although most of the macro code is set in "\MacroFont" we want to be
% able to switch to indicate module code set in "\AltMacroFont".
% "\macro@font" keeps track of which one we're using. We can't do the
% same thing sensibly in OFSS as in NFSS.
% \begin{macrocode}
\@ifundefined{AltMacroFont}{%
\if@compatibility
% \end{macrocode}
% Again have |\small| first if we are in compat mode.
% \changes{v1.9y}{1996/01/26}{Support compat mode}
% \begin{macrocode}
\def\AltMacroFont{\small
\usefont\encodingdefault
\ttdefault
\mddefault
\sldefault
}%
\else
\def\AltMacroFont{\fontencoding\encodingdefault
\fontfamily\ttdefault
\fontseries\mddefault
\fontshape\sldefault
\small
}%
\fi
}{}
% \end{macrocode}
% To allow changing the "\MacroFont" in the preamble we defer
% defining the internally used "\macro@font" until after the
% preamble.
% \changes{v2.0a}{1998/05/16}{Support changing \cs{MacroFont} in
% preamble}
% \begin{macrocode}
\AtBeginDocument{\let\macro@font\MacroFont}
% \end{macrocode}
% \end{macro}
% \end{macro}
%
% \begin{macro}{\check@module}
% \begin{macro}{\ifpm@module}
% \changes{v1.7a}{1992/03/12}{Added.}
% This is inserted by "\everypar" at the start of each macrocode line to
% check whether it starts with module information. (Such information is
% of the form "%<"\meta{switch}">", where the "%" must be at the
% start of the line and \meta{switch} comprises names with various
% possible separators and a possible leading "+", "-", "*" or "/"
% \cite{art:docstrip}. All that concerns us here is what the first
% character of \meta{switch} is.) First it checks the "pm@module"
% flag in case the previous line had a non-block module
% directive i.e., not "%<*" or "%</"; if it did we need to close the
% group it started and unset the flag. "\check@module" looks ahead at
% the next token and then calls "\ch@percent" to take action depending
% on whether or not it's a "%"; we don't want to expand the token at
% this stage. This is all done conditionally so it can be turned off
% if it causes problems with code that wasn't designed to be
% \texttt{docstrip}ped.
% \begin{macrocode}
\def\check@module{%
\ifcheck@modules
\ifpm@module \endgroup \pm@modulefalse \fi
\expandafter\futurelet\expandafter\next\expandafter\ch@percent
\fi}
\newif\ifpm@module
% \end{macrocode}
% \end{macro}
% \end{macro}
% \begin{macro}{\DontCheckModules}
% \begin{macro}{\CheckModules}
% \changes{v1.7a}{1992/03/12}{Added.}
% \begin{macro}{\ifcheck@modules}
% Here are two driver-file interface macros for turning the module
% checking on and off using the "check@modules" switch.
% \begin{macrocode}
\def\DontCheckModules{\check@modulesfalse}
\def\CheckModules{\check@modulestrue}
\newif\ifcheck@modules \check@modulestrue
% \end{macrocode}
% \end{macro}
% \end{macro}
% \end{macro}
% \begin{macro}{\ch@percent}
% \changes{v1.7a}{1992/03/12}{Added.}
% If the lookahead token in "\next" is $"%"_{12}$ we go on to check
% whether the following one is "<" and otherwise do nothing. Note the
% "\expandafter" to get past the "\fi".
% \begin{macrocode}
\def\ch@percent{%
\if \percentchar\next
\expandafter\check@angle
\fi}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\check@angle}
% \changes{v1.7a}{1992/03/12}{Added.}
% Before looking ahead for the "<" the "%" is gobbled by the
% argument here.
% \begin{macrocode}
\def\check@angle#1{\futurelet\next\ch@angle}
% \end{macrocode}
% \end{macro}
% \begin{macro}{\ch@angle}
% \changes{v1.7a}{1992/03/12}{Added.}
% \changes{v1.9k}{1994/02/22}{Have \texttt{<} active}
% If the current lookahead token is "<" we are defined to be
% processing a module directive can go on to look for "+" etc.;
% otherwise we must put back the gobbled "%". With \LaTeXe{}
% \texttt{<} is active so we have to be a bit careful.
% \begin{macrocode}
\begingroup
\catcode`\<\active
\gdef\ch@angle{\ifx<\next
\expandafter\ch@plus@etc
\else \percentchar \fi}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\ch@plus@etc}
% \begin{macro}{\check@plus@etc}
% \changes{v1.7a}{1992/03/12}{Added.}
% We now have to decide what sort of a directive we're dealing with
% and do the right thing with it.
% \begin{macrocode}
\gdef\ch@plus@etc<{\futurelet\next\check@plus@etc}
\gdef\check@plus@etc{%
\if +\next
\let\next\pm@module
\else\if -\next
\let\next\pm@module
\else\if *\next
\let\next\star@module
\else\if /\next
\let\next\slash@module
% \end{macrocode}
% At some point in the past the \texttt{docstrip} program was
% partly rewritten and at that time it also got support for a very
% special directive of the form |%<<| followed by an arbitrary
% string. This is used for ``verbatim'' inclusion in case of
% certain problem. We do not really attempt to pretty print that
% case but we need at least account for it since otherwise we get
% an error message since this is the only case where we will not
% have a closing |>|.
% \changes{v2.0n}{2001/05/16}{Partly support docstrip's ``verbatim''
% directive (pr/3331)}
% \begin{macrocode}
\else\ifx <\next
\percentchar
\else
\let\next\pm@module
\fi\fi\fi\fi\fi
\next}
\endgroup
% \end{macrocode}
% \end{macro}
% \end{macro}
% \begin{macro}{\pm@module}
% If we're not dealing with a block
% directive ("*" or "/") i.e., it's a single special line, we set
% everything up to the next ">" appropriately and then change to the
% special macro font inside a group which will be ended at the start
% of the next line. If the apparent module directive is missing the
% terminating ">" this will lose, but then so will the \texttt{docstrip}
% implementation. An alternative strategy would be to have
% "\pm@module" make ">" active and clear a flag set here to indicate
% processing the directive. Appropriate action could then be taken if
% the flag was found still to be set when processing the next line.
% \changes{v1.7a}{1992/03/12}{Added.}
% \changes{v1.7i}{1992/07/11}{Support for fonts depending on nesting.}
% \begin{macrocode}
\begingroup
\catcode`\~=\active
\lccode`\~=`\>
\lowercase{\gdef\pm@module#1~}{\pm@moduletrue
\Module{#1}\begingroup
% \end{macrocode}
% We switch to a special font as soon the nesting is higher than
% the current value of "\c@StandardModuleDepth". We do a local
% update to the "\guard@level" here which will be restored after
% the current input line.
% \begin{macrocode}
\advance\guard@level\@ne
\ifnum\guard@level>\c@StandardModuleDepth\AltMacroFont\fi
}
% \end{macrocode}
% \end{macro}
% \begin{macro}{\star@module}
% \begin{macro}{\slash@module}
% \changes{v1.7a}{1992/03/12}{Added.}
% \changes{v1.7f}{1992/05/16}{Take account of nested guards.}
% \changes{v1.7i}{1992/07/11}{Add counter to determine when to switch to
% special font.}
% If the start or end of a module {\em block\/} is indicated, after
% setting the guard we have to check whether a change in the macrocode
% font should be done. This will be the case if we are already inside
% a block or are ending the outermost block. If so, we globally
% toggle the font for subsequent macrocode sections between the normal
% and special form, switching to the new one immediately.
% \changes{v1.7i}{1992/07/17}{Support for fonts depending on module
% nesting}
% \begin{macrocode}
\lowercase{\gdef\star@module#1~}{%
\Module{#1}%
\global \advance \guard@level\@ne
\ifnum \guard@level>\c@StandardModuleDepth
\global\let\macro@font=\AltMacroFont \macro@font
\fi}
\catcode`\>=\active
\gdef\slash@module#1>{%
\Module{#1}%
\global \advance \guard@level\m@ne
\ifnum \guard@level=\c@StandardModuleDepth
\global\let\macro@font\MacroFont \macro@font
\fi
}
\endgroup
% \end{macrocode}
% \end{macro}
% \end{macro}
%
%
% \begin{macro}{\c@StandardModuleDepth}
% \changes{v1.7i}{1992/07/11}{Counter added.}
% Counter defining up to which level modules are considered part of
% the main code. If, for example, the whole code is surrounded by
% a |%<*package>| module we better set this counter to |1| to avoid
% getting the whole code be displayed in typewriter italic.
% \begin{macrocode}
\newcounter{StandardModuleDepth}
% \end{macrocode}
% \end{macro}
%
%
% \begin{macro}{\guard@level}
% \changes{v1.7f}{1992/05/16}{Added.}
% We need a counter to keep track of the guard nesting.
% \begin{macrocode}
\newcount \guard@level
% \end{macrocode}
% \end{macro}
% \begin{macro}{\Module}
% \changes{v1.7a}{1992/03/12}{Added.}
% \changes{v1.7d}{1992/04/25}{Use sans font for modules.}
% This provides a hook to determine the way the module directive is
% set. It gets as argument everything between the angle brackets.
% The default is to set the contents in sans serif text between
% $\langle\,\rangle$ with the special characters suitably "\mathcode"d
% by "\mod@math@codes". (You can't just set it in a sans text font
% because normally "|" will print as an em-dash.) This is done
% differently depending on whether we have the NFSS or the old one. In
% the latter case we can easily change "\fam" appropriately.
% \changes{v1.8c}{1993/10/25}{NFSS standard}
% \begin{macrocode}
\@ifundefined{Module}{%
% \end{macrocode}
% With NFSS what we probably {\em should\/} do is change to a new
% "\mathversion" but I (Dave Love) haven't spotted an easy way to
% do so correctly if the document uses a version other than
% "normal". (We need to know in what font to set the other
% groups.) This uses a new math alphabet rather than version and
% consequently has to worry about whether we're using
% \textsf{oldlfnt} or not. I expect there's a better
% way\ldots
% \begin{macrocode}
\def\Module#1{\mod@math@codes$\langle\mathsf{#1}\rangle$}
}{}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\mod@math@codes}
% \changes{v1.7c}{1992/03/26}{Added.}
% \changes{v2.1e}{2010/02/04}{Added mathcodes for +,-,:, and = (pr/4096)}
% As well as `words', the module
% directive text might contain any of the characters "*/+-,&|!()"
% for the current version of \textsf{docstrip}. We only need
% special action for two of them in the math code changing required
% above: "|" is changed to a "\mathop" (it's normally |"026A|) and
% "&" is also made a "\mathop", but in family 0. Remember that "&"
% will not have a special catcode when it's encountered.
% \begin{macrocode}
\def\mod@math@codes{\mathcode`\|="226A \mathcode`\&="2026
\mathcode`\-="702D \mathcode`\+="702B
\mathcode`\:="703A \mathcode`\=="703D }
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\mathsf}
% \changes{v1.7c}{1992/03/26}{Added.}
% \changes{v1.7d}{1992/04/25}{Use sans font for modules.}
% \changes{v1.7n}{1993/02/21}{\cs{sfmath} Renamed to \cs{mathsf}.}
% \changes{v1.8c}{1993/10/25}{NFSS standard}
% If NFSS is in use we need a new math alphabet which uses a sans serif
% font. To support both the release one and two of NFSS the alphabet
% was renamed to "\mathsf" which is defined in NFSS2.
% \begin{macrocode}
%\ifx\selectfont\undefined
%\else
% \ifx\mathsf\undefined
% \newmathalphabet*{\mathsf}{\sfdefault}{m}{n}\fi
%\fi
% \end{macrocode}
% \end{macro}
%
%
%
% \begin{macro}{\MacrocodeTopsep}
% \begin{macro}{\MacroIndent}
% In the code above, we have used two registers. Therefore we have
% to allocate them. The default values might be overwritten with
% the help of the |\DocstyleParms| macro.
% \changes{v1.5s}{1989/11/05}{Support for code line no. (Undoc)}
% \changes{v1.5y}{1990/02/24}{Default changed.}
% \changes{v1.6b}{1990/06/15}{\cs{rm} moved before \cs{scriptsize} to
% avoid unnecessary fontwarning.}
% \begin{macrocode}
\newskip\MacrocodeTopsep \MacrocodeTopsep = 3pt plus 1.2pt minus 1pt
\newdimen\MacroIndent
\settowidth\MacroIndent{\rmfamily\scriptsize 00\ }
% \end{macrocode}
% \end{macro}
% \end{macro}
%
%
%
%
% \begin{environment}{macrocode*}
% \begin{macro}{\endmacrocode*}
% Just as in the \textsf{verbatim} environment, there is also a
% `star' variant of the \textsf{macrocode} environment in which a
% space is shown by the symbol \verb*+ +. Until this moment, I
% have not yet used it (it will be used in the description of the
% definition of |\xmacro@code| below) but it's exactly on this one
% occasion {\em here\/} that you can't use it (cf.\ M\"unchhausens
% Marsh problem)\footnote{Karl Friedrich Hieronymus Frhr.\ v.\
% M\"unchhausen (*1720, \dag1797). Several books were written
% about fantastic adventures supposedly told by him (see
% \cite{book:Raspe} or \cite{book:Buerger}). In one story he
% escaped from the marsh by pulling himself out by his hair.}
% directly. Because of this, on this one occasion we'll cheat
% around the problem with an additional comment character. But now
% back to |\macrocode*|. We start with the macro |\macro@code|
% which prepares everything and then call the macro |\sxmacro@code|
% whose argument is terminated by the string
%\verb*+% \end{macrocode*}+.
% \begin{macrocode}
\@namedef{macrocode*}{\macro@code\sxmacro@code}
% \end{macrocode}
% As we know, |\sxmacro@code| and then |\end{macrocode*}|
% (the macro, not the string), will be executed, so that for a
% happy ending we still need to define the macro
% |\endmacrocode*|.
% \begin{macrocode}
\expandafter\let\csname endmacrocode*\endcsname = \endmacrocode
% \end{macrocode}
% \end{macro}
% \end{environment}
%
%
%
%
%
%
%
% \begin{macro}{\xmacro@code}
\catcode`\!=\catcode`\% ^^A In this section there must not be
^^A any exclamation marks.
^^A
% As already mentioned, the macro |\xmacro@code| expects an
% argument delimited by the string \verb*+% \end{macrocode}+. At
% the moment that this macro is called, the |\catcode| of
% \TeX's special characters are 12 (`other') or 13 (`active').
% Because of this we need to utilize a different escape character
% during the definition. This happens locally.
% \begin{macrocode*}
\begingroup
\catcode`\|=\z@ \catcode`\[=\@ne \catcode`\]=\tw@
% \end{macrocode*}
% Additionally, we need to ensure that the symbols in the above
% string contain the |\catcode|$\,$s which are available
% within the \textsf{macrocode} environment.
% \begin{macrocode*}
\catcode`\{=12 \catcode`\}=12
\catcode`\%=12 \catcode`\ =\active \catcode`\\=\active
!% \end{macrocode*}
! Next follows the actual definition of |\macro@code|;
! notice the
! use of the new escape character. We manage to get the argument
! surrounded by the string |\end{macrocode}|, but at the end
! however, in spite of the actual characters used during the
! definition of
! this macro, |\end| with the argument |{macrocode}|
! will be executed, to ensure a balanced environment.
! \begin{macrocode*}
|gdef|xmacro@code#1% \end{macrocode}[#1|end[macrocode]]
!% \end{macrocode*}
! \begin{macro}{\sxmacro@code}
! The definition of |\sxmacro@code| is completely analogous,
! only
! here a slightly different terminating string will be used.
! Note that the space is not active in this environment.
! \begin{macrocode}
|catcode`| =12
|gdef|sxmacro@code#1% \end{macrocode*}[#1|end[macrocode*]]
!% \end{macrocode}
! because the |\catcode| changes have been made local by
! commencing a
! new group, there now follows the matching |\endgroup|
! in a rather
! unusual style of writing.
! \begin{macrocode}
|endgroup
!% \end{macrocode}
\catcode`\!=12
% \end{macro}
% \end{macro}
%
%
%
%
% \subsection{Macros for the `documentation parts'}
%
%
% \begin{macro}{\DescribeMacro}
% \begin{macro}{\Describe@Macro}
% \changes{v1.5v}{1990/01/28}{Macro added.}
% \changes{v1.5j}{1989/06/09}{\cs{ignorespaces} added as a temporary
% fix}
% \begin{macro}{\DescribeEnv}
% \begin{macro}{\Describe@Env}
% \changes{v1.5v}{1990/01/28}{Macro added.}
% \changes{v1.5j}{1989/06/09}{\cs{ignorespaces} added as a temporary
% fix}
% The |\DescribeMacro| and |\DescribeEnv| macros should
% print their arguments in the margin and produce an index entry.
% We simply use |\marginpar| to get the desired result. This
% is however not the best solution because the labels might be
% slightly misplaced. One also might get a lot of `marginpar moved'
% messages which are hard-wired into the \LaTeX{} output
% routine.\footnote{It might be better to change these macros into
% environments like the \textsf{macro} environment.} First we change
% to horizontal mode if necessary. The \LaTeX{} macros
% |\@bsphack| and |\@esphack| are used to make those
% commands invisible (i.e.\ to normalize the surrounding space and
% to make the |\spacefactor| transparent).
% \changes{v1.5v}{1990/01/28}{\cs{MakePrivateLetters} added.}
% \begin{macrocode}
\def\DescribeMacro{\leavevmode\@bsphack
% \end{macrocode}
% When documenting the code for the \texttt{amstex.sty} option we
% encountered a bug: the |\catcode| of |@| was active and
% therefore couldn't be used in command names. So we first have to
% make sure that we get all |\catcode|s right by calling
% |\MakePrivateLetters| inside a group. Then we call
% |\Describe@Macro| to do the work.
% \changes{v2.0g}{1999/03/22}{Parse backslash as letter in argument
% to \cs{DescribeMacro}.}
% \changes{v2.0h}{1999/03/25}{Correct errors introduced in v2.0g.}
% \begin{macrocode}
\begingroup\MakePrivateLetters\Describe@Macro}
\def\Describe@Macro#1{\endgroup
\marginpar{\raggedleft\PrintDescribeMacro{#1}}%
% \end{macrocode}
% Note the use of |\raggedleft| to place the output flushed
% right. Finally we call a macro which produces the actual index
% entry and finish with |\@esphack| to leave no
% trace.\footnote{The whole mechanism won't work because
% of the \texttt{\bslash leavevmode} in front.
% As a temporary change \texttt{\bslash ignorespaces}
% is added.}
% \begin{macrocode}
\SpecialUsageIndex{#1}\@esphack\ignorespaces}
% \end{macrocode}
% The |\DescribeEnv| macro is completely analogous.
% \changes{v1.5v}{1990/01/28}{\cs{MakePrivateLetters} added.}
% \begin{macrocode}
\def\DescribeEnv{\leavevmode\@bsphack\begingroup\MakePrivateLetters
\Describe@Env}
\def\Describe@Env#1{\endgroup
\marginpar{\raggedleft\PrintDescribeEnv{#1}}%
\SpecialEnvIndex{#1}\@esphack\ignorespaces}
% \end{macrocode}
% To put the labels in the left margin we have to use the
% |\reversemarginpar| declaration. (This means that the
% \texttt{doc.sty} can't be used with all classes or packages.)
% We also
% make the |\marginparpush| zero and |\marginparwidth| suitably
% wide.
% \changes{v1.5d}{1989/04/28}{\cs{marginparwidth} setting added.}
% \begin{macrocode}
\reversemarginpar
\setlength\marginparpush{0pt} \setlength\marginparwidth{8pc}
% \end{macrocode}
% \end{macro}
% \end{macro}
% \end{macro}
% \end{macro}
%
% \begin{macro}{\bslash}
% \changes{v1.7a}{1992/02/26}{Moved \cs{bslash} documentation to `user
% interface' part}
% We start a new group in which to hide the alteration of
% |\catcode|$\,$s, and make \verb+|+ introduce commands,
% whilst |\| becomes an `other' character.
%
% \begin{macrocode}
{\catcode`\|=\z@ \catcode`\\=12
% \end{macrocode}
% Now we are able to define |\bslash| (globally) to generate a
% backslash of |\catcode| `other'. We then close this group,
% restoring original |\catcode|$\,$s.
% \SpecialEscapechar{\|}
% \begin{macrocode}
|gdef|bslash{\}}
% \end{macrocode}
% \end{macro}
%
%
%
% \begin{environment}{verbatim}
% \begin{environment}{verbatim*}
% \changes{v1.7i}{1992/07/12}{Added changed definition for verbatim!*.}
% The \textsf{verbatim} environment holds no secrets; it consists of
% the normal \LaTeX{} environment. We also set the
% |\@beginparpenalty| and change to the font given by
% |\MacroFont|.
% \begin{macrocode}
\def\verbatim{\@beginparpenalty \predisplaypenalty \@verbatim
\MacroFont \frenchspacing \@vobeyspaces \@xverbatim}
% \end{macrocode}
% We deal in a similar way with the star form of this environment.
% \begin{macrocode}
\@namedef{verbatim*}{\@beginparpenalty \predisplaypenalty \@verbatim
% \end{macrocode}
%
% \changes{v2.1j}{2019/11/03}{Kernel now sets up \cs{verbvisiblespace} (gh/205)}
% \changes{v2.1k}{2019/11/10}{Put the definition into the right command :-( (gh/205)}
% \begin{macrocode}
\@setupverbvisiblespace
\MacroFont \@vobeyspaces \@sxverbatim}
% \end{macrocode}
% \end{environment}
% \end{environment}
%
% \begin{macro}{\@verbatim}
% Additionally we redefine the |\@verbatim| macro so that it
% suppresses |%| characters at the beginning of the line. The
% first lines are copied literally from the \LaTeX{} format.
% \changes{v1.7i}{1992/07/12}{Added \cs{@@par} to clear possible
% \cs{parshape}.}
% \begin{macrocode}
\def\@verbatim{\trivlist \item[]\if@minipage\else\vskip\parskip\fi
\leftskip\@totalleftmargin\rightskip\z@
\parindent\z@\parfillskip\@flushglue\parskip\z@
\@@par
\@tempswafalse
% \end{macrocode}
% |\@verbatim| sets |^^M|, the end of line character, to
% be equal to |\par|. This control sequence is redefined
% here; |\@@par| is the paragraph primitive of \TeX.
% \changes{v1.7c}{1992/03/24}{Added \cs{interlinepenalty} to
% \cs{par} from verbatim.sty}
% \begin{macrocode}
\def\par{\if@tempswa\hbox{}\fi\@tempswatrue\@@par
\penalty\interlinepenalty
% \end{macrocode}
% We add a control sequence |\check@percent| to the definition
% of |\par| whose task it is to check for a percent character.
% \begin{macrocode}
\check@percent}%
% \end{macrocode}
% The rest is again copied literally from the \LaTeX{} format (less
% "\tt").
% \changes{v1.7a}{1992/02/26}{Removed redundant \cs{tt}.}
% \changes{v1.8b}{1993/09/21}{Changed to conform to new LaTeX verbatim,
% which handles more ligatures.}
% \begin{macrocode}
\obeylines
\let\do\do@noligs \verbatim@nolig@list
\let\do\@makeother \dospecials}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\check@percent}
% Finally we define |\check@percent|. Since this must compare a
% character with a percent sign we must first (locally) change
% percent's |\catcode| so that it is seen by \TeX. The definition
% itself is nearly trivial: grab the following character, check if
% it is a |%|, and insert it again if not. At the end of the
% \textsf{verbatim} environment this macro will peek at the next
% input line. In that case the argument to |\check@percent| might
% be a |\par| or a macro with arguments. Therefore we make the
% definition |\long| (|\par| allowed) and use the normal |\next|
% mechanism to reinsert the argument after the |\fi| if necessary.
% \changes{v1.5i}{1989/06/07}{Definition changed to `long'}
% \changes{v1.5i}{1989/06/07}{Macro \cs{next} used to guard against
% macro with arguments}
% There is a subtle problem here, the equal sign between
% |\next| and |#1| is actually necessary. Do you see why?
% The omission of this token once caused a funny error.
% \changes{v1.5u}{1989/11/14}{equal sign added.}
% \begin{macrocode}
{\catcode`\%=12
\long\gdef\check@percent#1{\ifx #1%\let\next\@empty \else
\let\next=#1\fi \next}}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\verb}
% \changes{v1.7a}{1992/02/27}{Now warns about newlines (from
% newdoc with `@noligs added).}
% \changes{v1.8b}{1993/09/21}{Changed to conform to new LaTeX \cs{verb}}
% We re-define "\verb" to check for newlines in its argument since a
% missing delimiter is difficult to detect in \DOC{} source.
% The code is the same as in \texttt{latex.tex} of September 19, 1993.
% Perhaps there should be a font-changing
% hook rather than just using "\ttfamily", but if so it probably should be
% different from "\MacroFont" since that normally includes "\small"
% and would look wrong inline.
% \changes{v1.7a}{1992/02/28}{Added math mode check (from verbatim.sty)}
% \begin{macrocode}
\def\verb{\relax\ifmmode\hbox\else\leavevmode\null\fi
\bgroup \let\do\do@noligs \verbatim@nolig@list
\ttfamily \verb@eol@error \let\do\@makeother \dospecials
\@ifstar{\@sverb}{\@vobeyspaces \frenchspacing \@sverb}}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\verb@balance@group}
% \begin{macro}{\verb@egroup}
% \begin{macro}{\verb@eol@error}
% \changes{v1.8b}{1993/09/21}{Renamed \cs{verb@err} to
% \cs{verb@eol@error}, as in new LaTeX verbatim.}
% \changes{v2.1n}{2021/05/28}{Use same error message text as in format}
% \begin{macrocode}
\let\verb@balance@group\@empty
\def\verb@egroup{\global\let\verb@balance@group\@empty\egroup}
\begingroup
\obeylines%
\gdef\verb@eol@error{\obeylines%
\def^^M{\verb@egroup\@latex@error{%
\noexpand\verb ended by end of line}\@ehc}}%
\endgroup
% \end{macrocode}
% \end{macro}
% \end{macro}
% \end{macro}
%
% \begin{macro}{\@sverb}
% \changes{v1.7a}{1992/02/27}{Added for \cs{verb} change.}
% \changes{v1.7a}{1992/02/28}{Now same as in verbatim.sty.}
% \changes{v1.8b}{1993/09/21}{Changed to conform to new LaTeX verbatim,
% which has better error trapping.}
% See \cite{art:verbatim} for commentary.
% \changes{v2.1j}{2019/11/03}{Use the kernel definition, no change needed (gh/205)}
% \begin{macrocode}
%\def\@sverb#1{%
% \catcode`#1\active \lccode`\~`#1%
% \gdef\verb@balance@group{\verb@egroup
% \@latex@error{Illegal use of \noexpand\verb command}\@ehc}%
% \aftergroup\verb@balance@group
% \lowercase{\let~\verb@egroup}}
% \end{macrocode}
% \end{macro}
%
%
% \begin{macro}{\verbatim@nolig@list}
% \begin{macro}{\do@noligs}
% These macros replace the old "\@noligs" mechanism by an
% extensible version to allow more ligatures to be added.
% \begin{macrocode}
\def\verbatim@nolig@list{\do\`\do\<\do\>\do\,\do\'\do\-}
\def\do@noligs#1{%
\catcode`#1\active
\begingroup
\lccode`\~=`#1\relax
\lowercase{\endgroup\def~{\leavevmode\kern\z@\char`#1}}}
% \end{macrocode}
% \end{macro}
% \end{macro}
%
%
% \begin{macro}{\macro}
% \begin{macro}{\m@cro@}
% \changes{v1.5v}{1990/01/28}{\cs{macro@} renamed to \cs{m@cro@}
% since AmSTeX
% defines another macro of the same name.}
% \begin{macro}{\macro@cnt}
% \label{page:macro} The \textsf{macro} environment is implemented as
% a \textsf{trivlist} environment, whereby in order that the macro
% names can be placed under one another in the margin
% (corresponding to the macro's nesting depth), the macro
% |\makelabel| must be altered. In order to store the nesting
% depth, we use a counter. We also need a counter to count the
% number of nested \textsf{macro} environments.
% \changes{v1.5k}{1989/08/17}{Fix for save stack problem.}
% \changes{v1.9k}{1994/02/22}{Fix probably no longer necessary}
% \begin{macrocode}
\newcount\macro@cnt \macro@cnt=0
% \end{macrocode}
% The environment takes an argument---the macro name to be
% described. Since this name may contain special `letters' we have
% to re-|\catcode| them before scanning the argument. This is done
% by the |\MakePrivateLetters| macro.
% \changes{v1.5k}{1989/08/17}{Fix for save stack problem.}
% \changes{v1.7a}{1992/02/26}{Catcode backslash to other (from newdoc).}
% \changes{v1.9k}{1994/02/22}{Don't omit extra group}
% \begin{macrocode}
\def\macro{\begingroup
\catcode`\\12
\MakePrivateLetters \m@cro@ \iftrue}
% \end{macrocode}
%
% \begin{environment}{environment}
% \changes{v1.8c}{1993/10/25}{Environment added}
% The ``environment'' environment will be implemented just like the
% ``macro'' environment flagging any differences in the code by
% passing |\iffalse| or |\iftrue| to the |\m@cro@| environment
% doing the actual work.
% \begin{macrocode}
\def\environment{\begingroup
\catcode`\\12
\MakePrivateLetters \m@cro@ \iffalse}
% \end{macrocode}
% \end{environment}
%
% After scanning the argument we close the group to get the normal
% |\catcode|$\,$s back. Then we assign a special value to
% |\topsep| and start a \textsf{trivlist} environment.
% \changes{v1.5f}{1989/05/07}{MacroTopsep parameter added.}
% \changes{v1.5k}{1989/08/17}{Fix for save stack problem.}
% \changes{v1.8c}{1993/10/25}{Support ``environment'' env}
% \changes{v1.9k}{1994/02/22}{Remove \cs{macro@level}}
% \begin{macrocode}
\long\def\m@cro@#1#2{\endgroup \topsep\MacroTopsep \trivlist
% \end{macrocode}
% We also save the name being described in |\saved@macroname| for
% use in conjunction with the |\changes| macro.
% \begin{macrocode}
\edef\saved@macroname{\string#2}%
#1
% \end{macrocode}
% If documenting an environment we put is name in |\saved@indexname|
% otherwise the name without the backslash.
% \changes{v2.1g}{2016/02/15}{Use \cs{saved@indexname}}
% \begin{macrocode}
\let\saved@indexname\saved@macroname
\else
\edef\saved@indexname{\expandafter\@gobble\string#2}%
\fi
% \end{macrocode}
% Now there follows a variation of |\makelabel| which is used
% should the environment not be nested, or should it lie between
% two successive |\begin{macro}| instructions or explanatory
% text. One can recognize this with the switch |\if@inlabel|
% which will be |true| in the case of successive |\item|
% commands.
% \begin{macrocode}
\def\makelabel##1{\llap{##1}}%
% \end{macrocode}
% If |@inlabel| is |true| and if $\verb=\macro@cnt= > 0$
% then the above definition needs to be changed, because in this
% case \LaTeX{} would otherwise put the labels all on the same line
% and this would lead to them being overprinted on top of each
% other. Because of this |\makelabel| needs to be redefined
% in this case.
% \begin{macrocode}
\if@inlabel
% \end{macrocode}
% If |\macro@cnt| has the value $1$, then we redefine
% |\makelabel| so that the label will be positioned in the
% second line of the margin. As a result of this, two macro names
% appear correctly, one under the other. It's important whilst
% doing this that the generated label box is not allowed to have
% more depth than a normal line since otherwise the distance
% between the first two text lines of \TeX{} will be incorrectly
% calculated. The definition should then look like:
%\begin{verbatim}
% \def\makelabel##1{\llap{\vtop to \baselineskip
% {\hbox{\strut}\hbox{##1}\vss}}}
%\end{verbatim}
% Completely analogous to this is the case where labels need to be
% placed one under the other. The lines above are only an example
% typeset with the \textsf{verbatim} environment. To produce the real
% definition we save the value of |\macro@cnt| in
% |\count@| and empty the temp macro |\@tempa| for later
% use.
% \begin{macrocode}
\let\@tempa\@empty \count@\macro@cnt
% \end{macrocode}
% In the following loop we append for every already typeset label
% an |\hbox{\strut}| to the definition of |\@tempa|.
% \begin{macrocode}
\loop \ifnum\count@>\z@
\edef\@tempa{\@tempa\hbox{\strut}}\advance\count@\m@ne \repeat
% \end{macrocode}
% Now be put the definition of |\makelabel| together.
% \changes{v1.5b}{1989/04/27}{vbox to vtop changed in makelabel (test)}
% \changes{v1.5e}{1989/04/28}{ht strutbox changed to baselineskip
% (test)}
% \begin{macrocode}
\edef\makelabel##1{\llap{\vtop to\baselineskip
{\@tempa\hbox{##1}\vss}}}%
% \end{macrocode}
% Next we increment the value of the nesting depth counter. This
% value inside the \textsf{macro} environment is always at least one
% after this point, but its toplevel definition is zero. Provided
% this environment has been used correctly, $|\macro@cnt|=0$
% should not occur when |@inlabel|=\textsf{true}. It is
% however possible if this environment is used within other list
% environments (but this would have little point).
% \begin{macrocode}
\advance \macro@cnt \@ne
% \end{macrocode}
% If |@inlabel| is false we reset |\macro@cnt| assuming
% that there is enough room to print the macro name without
% shifting.
% \begin{macrocode}
\else \macro@cnt\@ne \fi
% \end{macrocode}
% Now the label will be produced using |\item|. The following
% line is only a hack saving the day until a better solution is
% implemented. We have to face two problems: the argument might be
% a |\par| which is forbidden in the argument of other macros
% if they are not defined as |\long|, or it is something like
% |\iffalse| or |\else|, i.e.\ something which will be
% misinterpreted when \TeX{} is skipping conditional text. In both
% cases |\item| will bomb, so we protect the argument by using
% |\string|.
% \begin{macrocode}
\edef\@tempa{\noexpand\item[%
% \end{macrocode}
% Depending on whether we are inside a ``macro'' or ``environment''
% environment we use |\PrintMacroName| or |\PrintEnvName| to
% display the name.
% \begin{macrocode}
#1%
\noexpand\PrintMacroName
\else
\noexpand\PrintEnvName
\fi
{\string#2}]}%
\@tempa
% \end{macrocode}
% At this point we also produce an index entry. Because it is not
% known which index sorting program will be used, we do not use the
% command |\index|, but rather a command
% |\SpecialMainIndex| after advancing the counter for indexing
% by line number. This may be redefined by the user in
% order to generate an index entry which will be understood by the
% index program in use (note the definition of
% |\SpecialMainIndex| for our installation).
% \changes{v1.5s}{1989/11/05}{Support for code line no. (Undoc)}
% \changes{v1.9u}{1995/08/06}{Removed brace group which
% killed \cs{DoNotIndex}}
% We advance the current codeline number and after producing an
% index entry revert to the original value
% \begin{macrocode}
\global\advance\c@CodelineNo\@ne
% \end{macrocode}
% Again the macro to call depends on the environment we are
% actually in.
% \begin{macrocode}
#1%
\SpecialMainIndex{#2}\nobreak
\DoNotIndex{#2}%
\else
\SpecialMainEnvIndex{#2}\nobreak
\fi
\global\advance\c@CodelineNo\m@ne
% \end{macrocode}
% The |\nobreak| is needed to prevent a page break after the
% |\write| produced by the |\SpecialMainIndex| macro. We
% exclude the new macro in the cross-referencing feature, to
% prevent spurious non-main entry references. Regarding possibly
% problematic arguments, the implementation takes
% care of |\par| and the conditionals are uncritical.
% \changes{v1.7a}{1992/03/02}{Removed redundant code checking for
% \cs{par}.}^^A
%
% Because the space symbol should be ignored between the
% |\begin{macro}{...}| and the following text we must take
% care of this with |\ignorespaces|.
% \begin{macrocode}
\ignorespaces}
% \end{macrocode}
% \end{macro}
% \end{macro}
% \end{macro}
%
%
%
% \begin{macro}{\endmacro}
% \begin{macro}{\endenvironment}
% Older releases of this environment omit the |\endgroup| token,
% when being nested. This was done to avoid unnecessary stack usage.
% However it does not work if \textsf{macro} and
% \textsf{environment} environments are mixed, therefore we now
% use a simpler approach.
% \changes{v1.5k}{1989/08/17}{Fix for save stack problem.}
% \changes{v1.9k}{1994/02/22}{Don't checkfor nesting}
% \begin{macrocode}
\let\endmacro \endtrivlist
\let\endenvironment\endmacro
% \end{macrocode}
% \end{macro}
% \end{macro}
%
% \begin{macro}{\MacroTopsep}
% Here is the default value for the |\MacroTopsep| parameter
% used above.
% \begin{macrocode}
\newskip\MacroTopsep \MacroTopsep = 7pt plus 2pt minus 2pt
% \end{macrocode}
% \end{macro}
%
%
%
%
%
% \subsection{Formatting the margin}
%
% The following three macros should be user definable.
% Therefore we define those macros only if they have not already
% been defined.
%
% \begin{macro}{\PrintMacroName}
% \begin{macro}{\PrintEnvName}
% \begin{macro}{\PrintDescribeMacro}
% \begin{macro}{\PrintDescribeEnv}
% The formatting of the macro name in the left margin is done by
% these macros. We first set a |\strut| to get the height and
% depth of the normal lines. Then we change to the
% |\MacroFont| using |\string| to |\catcode| the
% argument to other (assuming that it is a macro name). Finally we
% print a space. The font change remains local since this macro
% will be called inside an |\hbox|.
% \begin{macrocode}
\@ifundefined{PrintMacroName}
{\def\PrintMacroName#1{\strut \MacroFont \string #1\ }}{}
% \end{macrocode}
% We use the same formatting conventions when describing a macro.
% \begin{macrocode}
\@ifundefined{PrintDescribeMacro}
{\def\PrintDescribeMacro#1{\strut \MacroFont \string #1\ }}{}
% \end{macrocode}
% To format the name of a new environment there is no need to use
% |\string|.
% \begin{macrocode}
\@ifundefined{PrintDescribeEnv}
{\def\PrintDescribeEnv#1{\strut \MacroFont #1\ }}{}
\@ifundefined{PrintEnvName}
{\def\PrintEnvName#1{\strut \MacroFont #1\ }}{}
% \end{macrocode}
% \end{macro}
% \end{macro}
% \end{macro}
% \end{macro}
%
%
%
% \subsection{Creating index entries by scanning `macrocode'}
%
% The following macros ensure that index entries are created for each
% occurrence of a \TeX-like command (something starting with
% `|\|') providing indexing has been turned on with "\PageIndex"
% or "\CodelineIndex". With the default definitions of
% |\SpecialMainIndex|, etc., the index file generated is
% intended to be processed by Chen's \textsf{makeindex} program
% \cite{art:Chen}.
%
%
% Of course, in {\em this\/} package file itself we've sometimes had to
% make \verb+|+ take the r\^ole of \TeX's escape character to
% introduce command names at places where |\| has to belong to
% some other category. Therefore, we may also need to recognize
% \verb+|+ as the introducer for a command when setting the text
% inside the \textsf{macrocode} environment. Other users may have the
% need to make similar reassignments for their macros.
%
%
% \begin{macro}{\SpecialEscapechar}\label{sect:specialescapechar}
% \begin{macro}{\active@escape@char}
% \begin{macro}{\special@escape@char}
% The macro |\SpecialEscapechar| is used to denote a special escape
% character for the next \textsf{macrocode} environment. It has one
% argument---the new escape character given as a `single-letter'
% control sequence. Its main purpose is defining
% |\special@escape@char| to produce the chosen escape character
% |\catcode|$\,$d to 12 and |\active@escape@char| to produce the
% same character but with |\catcode| 13.
%
% The macro |\special@escape@char| is used to {\em print\/}
% the escape character while |\active@escape@char| is needed
% in the definition of |\init@crossref| to start the scanning
% mechanism.
%
% In the definition of |\SpecialEscapechar| we need an
% arbitrary character with |\catcode| 13. We use `\~{}' and
% ensure that it is active. The |\begingroup| is used to make
% a possible change local to the expansion of
% |\SpecialEscapechar|.
% \changes{v1.7g}{1992/06/19}{Making tilde active moved outside
% definition}
% \begin{macrocode}
\begingroup
\catcode`\~\active
\gdef\SpecialEscapechar#1{%
\begingroup
% \end{macrocode}
% Now we are ready for the definition of
% |\active@escape@char|. It's a little tricky: we first
% define locally the uppercase code of `\~{}' to be the new escape
% character.
% \begin{macrocode}
\uccode`\~`#1%
% \end{macrocode}
% Around the definition of |\active@escape@char| we place an
% |\uppercase| command. Recall that the expansion of
% |\uppercase| changes characters according to their
% |\uccode|, but leaves their |\catcode|$\,$s untouched
% (cf.\ \TeX{}book page 41).
% \begin{macrocode}
\uppercase{\gdef\active@escape@char{~}}%
% \end{macrocode}
% The definition of |\special@escape@char| is easier, we use
% |\string| to |\catcode| the argument of
% |\SpecialEscapechar| to 12 and suppress the preceding
% |\escapechar|.
% \begin{macrocode}
\escapechar\m@ne \xdef\special@escape@char{\string#1}%
% \end{macrocode}
% Now we close the group and end the definition: the value of
% |\escapechar| as well as the |\uccode| and
% |\catcode| of `\~{}' will be restored.
% \begin{macrocode}
\endgroup}
\endgroup
% \end{macrocode}
% \end{macro}
% \end{macro}
% \end{macro}
%
%
%
%
% \begin{macro}{\init@crossref}
% The replacement text of |\init@crossref| should fulfill the
% following tasks:
% \begin{itemize}
% \parindent4em
% \item[1)]
% |\catcode| all characters used in macro names to
% 11 (i.e.\ `letter').
% \item[2)]
% |\catcode| the `|\|' character to 13
% (i.e.\ `active').
% \item[3a)]
% |\let| the `|\|' equal |\scan@macro|
% (i.e.\ start the macro scanning mechanism) if there is
% no special escape character (i.e.\ the
% |\special@escape@char| is `|\|').
% \item[3b)]
% Otherwise |\let| it equal |\bslash|, i.e.\
% produce a printable |\|.
% \item[4)]
% Make the \meta{special escape character} active.
% \item[5)]
% |\let| the active version of the special escape
% character
% (i.e.\ the expansion of |\active@escape@char|) equal
% |\scan@macro|.
% \end{itemize}
% The reader might ask why we bother to |\catcode| the
% `|\|' first to 12 (at the end of |\macro@code|) then
% re-|\catcode| it to 13 in order to produce a $|\|_{12}$
% in case 3b) above. This is done because we have to ensure that
% `|\|' has |\catcode| 13 within the \textsf{macrocode}
% environment. Otherwise the delimiter for the argument of
% |\xmacro@code| would not be found (parameter matching
% depends on |\catcode|$\,$s).
%
% Therefore we first re-|\catcode| some characters.
% \begin{macrocode}
\begingroup \catcode`\|=\z@ \catcode`\\=\active
% \end{macrocode}
% We carry out tasks 2) and 3b) first.
% \SpecialEscapechar{\|}
% \begin{macrocode}
|gdef|init@crossref{|catcode`|\|active |let\|bslash
% \end{macrocode}
% Because of the popularity of the `|@|' character as a
% `letter' in macros, we normally have to change its
% |\catcode| here, and thus fulfill task 1). But the macro
% designer might use other characters as private letters as well,
% so we use a macro to do the |\catcode| switching.
% \SpecialEscapechar\|
% \begin{macrocode}
|MakePrivateLetters
% \end{macrocode}
% Now we |\catcode| the special escape character to 13 and
% |\let| it equal |\scan@macro|, i.e.\ fulfill tasks 4)
% and 5). Note the use of |\expandafter| to insert the chosen
% escape character saved in |\special@escape@char| and
% |\active@escape@char|.
% \SpecialEscapechar\|
% \begin{macrocode}
|catcode|expandafter`|special@escape@char|active
|expandafter|let|active@escape@char|scan@macro}
|endgroup
% \end{macrocode}
% If there is no special escape character, i.e.\ if
% |\SpecialEscapechar| is |\\|, the second last line will
% overwrite the previous definition of $|\|_{13}$. In this
% way all tasks are fulfilled.
%
% For happy documenting we give default values to
% |\special@escape@char| and |\active@escape@char| with
% the following line:
% \begin{macrocode}
\SpecialEscapechar{\\}
% \end{macrocode}
% \end{macro}
%
%
%
% \begin{macro}{\MakePrivateLetters}
% Here is the default definition of this command, which makes just
% the |@| into a letter. The user may change it if he/she
% needs more or other characters masquerading as letters.
% \begin{macrocode}
\@ifundefined{MakePrivateLetters}
{\let\MakePrivateLetters\makeatletter}{}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\close@crossref}
% At the end of a cross-referencing part we prepare ourselves for
% the next one by setting the escape character to `|\|'.
% \begin{macrocode}
\def\close@crossref{\SpecialEscapechar\\}
% \end{macrocode}
% \end{macro}
%
%
%
%
% \subsection{Macros for scanning macro names}
%
% \begin{macro}{\scan@macro}
% \changes{v1.5k}{1989/09/04}{Support for checksum added.}
% \begin{macro}{\macro@namepart}
% The |\init@crossref| will have made |\active| our
% |\special@escape@char|, so that each
% |\active@escape@char| will invoke |\scan@macro| when
% within the \textsf{macrocode} environment. By this means, we can
% automatically add index entries for every \TeX-like command which
% is met whilst setting (in verbatim) the contents of
% \textsf{macrocode} environments.
% \begin{macrocode}
\def\scan@macro{%
% \end{macrocode}
% First we output the character which triggered this macro. Its
% version |\catcode|$\,$d to 12 is saved in
% |\special@escape@char|. We also call |\step@checksum|
% to generate later on a proper check-sum (see section
% \ref{sec:checksum} for details).
% \begin{macrocode}
\special@escape@char
\step@checksum
% \end{macrocode}
% If the \textsf{macrocode} environment contains, for example, the
% command |\\|, the second |\| should not start the
% scanning mechanism. Therefore we use a switch to decide if
% scanning of macro names is allowed.
% \begin{macrocode}
\ifscan@allowed
% \end{macrocode}
% The macro assembles the letters forming a \TeX\ command in
% |\macro@namepart| so this is initially cleared; we then set
% |\next| to the \textit{first\/} character following the
% |\| and call |\macro@switch| to determine whether that
% character is a letter or not.
% \begin{macrocode}
\let\macro@namepart\@empty
\def\next{\futurelet\next\macro@switch}%
% \end{macrocode}
% As you recognize, we actually did something else, because we have
% to defer the |\futurelet| call until after the final
% |\fi|. If, on the other hand, the scanning is disabled we
% simply |\let| |\next| equal `empty'.
% \begin{macrocode}
\else \let\next\@empty \fi
% \end{macrocode}
% Now we invoke |\next| to carry out what's needed.
% \begin{macrocode}
\next}
% \end{macrocode}
% \end{macro}
% \end{macro}
%
%
% \begin{macro}{\ifscan@allowed}
% \begin{macro}{\scan@allowedtrue}
% \begin{macro}{\scan@allowedfalse}
% |\ifscan@allowed| is the switch used above to determine if
% the |\active@escape@char|\SpecialIndex{\active@escape@char}
% should start the macro scanning mechanism.
% \begin{macrocode}
\newif\ifscan@allowed \scan@allowedtrue
% \end{macrocode}
% \end{macro}
% \end{macro}
% \end{macro}
%
%
% \begin{macro}{\EnableCrossrefs}
% \begin{macro}{\DisableCrossrefs}
% At this point we might define two macros which allow the user to
% disable or enable the cross-referencing mechanism. Processing of
% files will be faster if only main index entries are generated
% (i.e., if |\DisableCrossrefs| is in force).
% \begin{macrocode}
\def\DisableCrossrefs{\@bsphack\scan@allowedfalse\@esphack}
% \end{macrocode}
% The macro |\EnableCrossrefs| will also disable any
% |\DisableCrossrefs| command encountered afterwards.
% \begin{macrocode}
\def\EnableCrossrefs{\@bsphack\scan@allowedtrue
\def\DisableCrossrefs{\@bsphack\@esphack}\@esphack}
% \end{macrocode}
% \end{macro}
% \end{macro}
%
%
%
%
% \begin{macro}{\macro@switch}
% Now that we have the character which follows the escape character
% (in |\next|), we can determine whether it's a `letter'
% (which probably includes |@|).
%
% If it is, we let |\next| invoke a macro which assembles the
% full command name.
% \begin{macrocode}
\def\macro@switch{\ifcat\noexpand\next a%
\let\next\macro@name
% \end{macrocode}
% Otherwise, we have a `single-character' command name. For all
% those single-character names, we use |\short@macro| to
% process them into suitable index entries.
% \begin{macrocode}
\else \let\next\short@macro \fi
% \end{macrocode}
% Now that we know what macro to use to process the macro name, we
% invoke it~\ldots
% \begin{macrocode}
\next}
% \end{macrocode}
% \end{macro}
%
%
% \begin{macro}{\short@macro}
% \changes{v1.5c}{1989/04/27}{Corrected bad bug by putting the
% scan@allowedfalse macro before printing
% the argument.}
% \changes{v1.7a}{1992/03/10}{Ensure character stored in
% \cs{macro@namepart} as `letter' so index exclusion works.}
% This macro will be invoked (with a single character as parameter)
% when a single-character macro name has been spotted whilst
% scanning within the \textsf{macrocode} environment.
%
% First we take a look at the |\index@excludelist| to see
% whether this macro name should produce an index entry. This is
% done by the |\ifnot@excluded| macro which assumes that the
% macro name is saved in |\macro@namepart|. The character
% mustn't be stored with a special category code or exclusion from
% the index won't work, so we employ the case-changing trick used
% elsewhere. Since the argument might be an active character,
% |\string| is used to normalize it.
% \changes{v2.0e}{1998/12/28}{Correctly use the case-changing trick.}
% \begin{macrocode}
\begingroup
\catcode`\&=12
\gdef\short@macro#1{\begingroup
\uccode`\&=\expandafter`\string#1%
\uppercase{\def\x{\def\macro@namepart{&}}}%
\expandafter\endgroup\x
\ifnot@excluded
% \end{macrocode}
% If necessary the index entry is produced by the macro
% |\produce@index|. Depending on the actual character seen,
% this macro has to do different things, so we pass the character
% as an argument.
% \begin{macrocode}
\produce@index{#1}\fi
% \end{macrocode}
% Then we disable the cross-referencing mechanism with
% |\scan@allowedfalse| and print the actual character. The
% index entry was generated first to ensure that no page break
% intervenes (recall that a |^^M| will start a new line).
% \begin{macrocode}
\scan@allowedfalse#1%
% \end{macrocode}
% After typesetting the character we can safely enable the
% cross-referencing feature again. Note that this macro won't be
% called (since |\macro@switch| won't be called) if
% cross-referencing is globally disabled.
% \begin{macrocode}
\scan@allowedtrue }
\endgroup
% \end{macrocode}
% \end{macro}
%
%
%
% \begin{macro}{\produce@index}
% \changes{v1.4s}{1989/04/23}{Added noexpand to all
% \cs{if} tests
% to avoid garbage produced by new active chars}
% \changes{v1.4s}{1989/04/23}{Used \texttt{\protect\bslash string} for
% the same reason.}
% \changes{v1.5c}{1989/04/27}{Corrected bad bug by placing the
% scan@allowedfalse macro into short@macro}
% This macro is supposed to generate a suitable |\SortIndex|
% command for a given single-letter control sequence. We test
% first for the cases which involve active characters (i.e.\ the
% backslash, the special escape character (if any), the space and
% the |^^M|). Using the |\if| test (testing for
% character codes), we have to ensure that the argument isn't
% expanded.
% \begin{macrocode}
\def\produce@index#1{%
\if\noexpand#1\special@escape@char
% \end{macrocode}
% If the character is the special escape character (or the
% `|\|' in case there was none) the |\it@is@a| macro is
% used to produce the actual |\SortIndex| call.
% \begin{macrocode}
\scan@allowedfalse \it@is@a\special@escape@char \else
% \end{macrocode}
% Next comes the test for a `|\|' which must be the
% $|\|_{13}$ expanding to |\bslash|.
% \begin{macrocode}
\if\noexpand#1\bslash \it@is@a\bslash \else
% \end{macrocode}
% Another possibility is \verb*+ +$_{13}$. Recall that |\space|
% produces a \verb*+ +$_{10}$.
% \begin{macrocode}
\if\noexpand#1\space \it@is@a\space \else
% \end{macrocode}
% The last\footnote{Well, it isn't the last active character after
% all. I added \texttt{\bslash @noligs} some days ago and now
% \texttt{`} too is active. So we have to make sure that such
% characters don't get expanded in the index.} possibility of an
% active character is |^^M|\@. In this case we don't test for
% character codes, since it is easier to look if the character is
% equal to |\par|. (We are inside the \textsf{macrocode}
% environment.)
% \begin{macrocode}
\ifx#1\par
% \end{macrocode}
% If we end up here we have just scanned a |\^^M| or something
% similar. Since this will be treated like \verb*+\ + by \TeX{} we
% produce a corresponding index entry.
% \begin{macrocode}
\it@is@a\space \else
% \end{macrocode}
% If it is the token |\relax| we do nothing. This can't happen
% when the `doc' package is used in the way described here, but was
% added to allow extensions like the \texttt{idxverb} option.
% \changes{v1.5t}{1989/11/14}{Added \cs{relax} as a possible token to
% allow extensions.}
% \begin{macrocode}
\ifx#1\relax \else
% \end{macrocode}
% The next three branches are needed because of bugs in
% our \textsf{makeindex} program. You can't produce unbalanced index
% entries\footnote{This is possible for \TeX{} if you use
% \texttt{\string{$_{12}$ \rmfamily or
% \ttfamily\string}$_{12}$},
% but \textsf{makeindex} will complain.}
% and you have to double a percent character. To get around these
% restrictions we use special macros to produce the |\index|
% calls.\footnote{Brian \textsc{Hamilton Kelly} has written fixes for
% all three
% bugs. When they've found their way through all
% installations,
% the lines above will be removed. See
% page~\pageref{bug:fixes} if you already have them.
% (I'm not sure which versions incorporate these, but
% 2.11 is OK. See also
% \pageref{makeindex:version}.)}
% \begin{macrocode}
\if\noexpand#1\bgroup \LeftBraceIndex \else
\if\noexpand#1\egroup \RightBraceIndex \else
\if\noexpand#1\percentchar \PercentIndex \else
% \end{macrocode}
% All remaining characters are used directly to produce their index
% entries. This is possible even for the characters which have
% special meanings in the index program, provided we quote the
% characters. (This is correctly done in |\it@is@a|.)
% \begin{macrocode}
\it@is@a{\string#1}%
% \end{macrocode}
% We now need a whole pile of |\fi|$\,$s to match up with
% the |\if|$\,$s.
% \begin{macrocode}
\fi \fi \fi \fi \fi \fi \fi \fi}
% \end{macrocode}
% \end{macro}
%
%
%
% \begin{macro}{\macro@name}
% We now come to the macro which assembles command names which
% consist of one or more `letters' (which might well include
% |@| symbols, or anything else which has a |\catcode| of
% 11).
%
% To do this we add the `letter' to the existing definition of
% |\macro@namepart| (which you will recall was originally set
% to |\@empty|).
% \begin{macrocode}
\def\macro@name#1{\edef\macro@namepart{\macro@namepart#1}%
% \end{macrocode}
% Then we grab hold of the {\em next\/} single character and let
% |\more@macroname| determine whether it belongs to the letter
% string forming the command name or is a `non-letter'.
% \begin{macrocode}
\futurelet\next\more@macroname}
% \end{macrocode}
% \end{macro}
%
%
%
%
%
% \begin{macro}{\more@macroname}
%
% This causes another call of |\macro@name| to add in the next
% character, if it is indeed a `letter'.
% \begin{macrocode}
\def\more@macroname{\ifcat\noexpand\next a%
\let\next\macro@name
% \end{macrocode}
% Otherwise, it finishes off the index entry by invoking
% |\macro@finish|.
% \begin{macrocode}
\else \let\next\macro@finish \fi
% \end{macrocode}
% Here's where we invoke whatever macro was |\let| equal to
% |\next|.
% \begin{macrocode}
\next}
% \end{macrocode}
% \end{macro}
%
%
%
%
%
% \begin{macro}{\macro@finish}
% When we've assembled the full `letter'-string which forms the
% command name, we set the characters forming the entire command
% name, and generate an appropriate |\index| command (provided
% the command name is not on the list of exclusions). The
% `|\|' is already typeset; therefore we only have to output
% all `letters' saved in |\macro@namepart|.
% \begin{macrocode}
\def\macro@finish{%
\macro@namepart
% \end{macrocode}
% Then we call |\ifnot@excluded| to decide whether we have to
% produce an index entry. The construction with |\@tempa| is
% needed because we want the expansion of |\macro@namepart| in
% the |\index| command.\footnote{The \texttt{\bslash index}
% command will expand its argument in the \texttt{\bslash output}
% routine. At this time \texttt{\bslash macro@namepart} might have a
% new value.}
% \begin{macrocode}
\ifnot@excluded
\edef\@tempa{\noexpand\SpecialIndex{\bslash\macro@namepart}}%
\@tempa \fi}
% \end{macrocode}
% \end{macro}
%
%
%
%
%
% \subsection[The index exclude list]{The index exclude
% list\footnotemark}
% \footnotetext{Warning: the incomplete commentary on
% \texttt{\bslash DoNotIndex} and the macros it calls
% was written by Dave Love.}
%
% The internal form of the index exclude list is
% \begin{quote}
% \meta{macro name}|,|\meta{macro name}|,|
% \ldots|,|
% \end{quote}
% where \meta{macro name} is a macro name like
% $"\"_{12}"p"{_{11}}"@"_{11}$ or $"\"_{12}"$"_{11}$. Note that the "\"
% has category `other' and the other characters in the name are all
% `letter', regardless of their normal category.
%
% \begin{macro}{\DoNotIndex}
% This macro is used to suppress macro names in the index. It
% starts off with a new group because we have to change the
% |\catcode|$\,$s of all characters which belong to `letters'
% while macros are defined.
% \begin{macrocode}
\def\DoNotIndex{\begingroup \MakePrivateLetters
\catcode`\\12
% \end{macrocode}
% Then we call the macro which actually reads the argument given by
% the user.
% \begin{macrocode}
\do@not@index}
% \end{macrocode}
% \end{macro}
%
%
%
% \begin{macro}{\do@not@index}
% We make the |\do@not@index| macro |\long|
% since the user might want to exclude the |\par|
% macro.
% \begin{macrocode}
\long\def\do@not@index#1{%
% \end{macrocode}
% It just adds to a token list after finishing the group in which
% the catcodes were changed.
% \changes{v1.7a}{1992/02/26}{Replaced with newdoc version.}
% \begin{macrocode}
\endgroup
\addto@hook\index@excludelist{#1,}}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\addto@hook}
% The code for adding tokens (the second argument) to a token list
% (the first argument) is taken from~\cite{art:verbatim}, but it needs
% to be "\long" in case "\par" is amongt the tokens.
% \begin{macrocode}
\long\def\addto@hook#1#2{#1\expandafter{\the#1#2}}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\index@excludelist}
% We need an initially-empty register for the excluded list.
% \begin{macrocode}
\newtoks\index@excludelist
\index@excludelist{}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\ifnot@excluded}
% \changes{v1.7a}{1992/02/26}{Replaced with newdoc version.}
% \begin{macro}{\expanded@notin}
% Now we take a look at the |\index@excludelist| to see
% whether a macro name saved in |\macro@namepart| should
% produce an index entry. This macro is a pseudo |\if|; it
% should expand to |\iftrue| or |\iffalse| depending on
% the contents of |\index@excludelist|.
% \begin{macrocode}
\begingroup
% \end{macrocode}
% First we change "\catcode"s so that "\" is `other' and "|" a
% temporary for the escape character. This is necessary since our
% macro names are stored that way in the "\index@excludelist".
% \begin{macrocode}
\catcode`\|=0%
\catcode`\\=12
% \end{macrocode}
% Then we define "\ifnot@excluded" to call "\expanded@notin" with
% two arguments: the first is the string "\" followed by the
% contents of "\macro@namepart" followed by a "," and the second is
% "\the" followed by "\index@excludelist". To achieve the expansion
% of "\macro@namepart", i.e.\ to pass its contents, we need a
% suitable number of "\expandafter"s.
% \SpecialEscapechar{\|}
% \begin{macrocode}
|gdef|ifnot@excluded{|expandafter
|expanded@notin|expandafter{|expandafter
\|macro@namepart,}{|the|index@excludelist}}
|endgroup
% \end{macrocode}
% The macro "\expanded@notin" now does the dirty work. It first
% defines a macro "\in@@" with a very special parameter text. If
% you look closely "\in@@" has three arguments, the first one is
% delimited by the first argument of "\expanded@notin" (i.e.\ by
% the string starting with a "\" and ending with a "," above), the
% second is undelimited (which means that it will get the next
% token after our string, and the third is delimited again and will
% get the rest up to the token "\in@@". In other words the token
% "\in@@" is also used as a delimiter.
% \begin{macrocode}
\def\expanded@notin#1#2{%
\def\in@@##1#1##2##3\in@@{%
% \end{macrocode}
% Now the replacement text simply compares the second argument
% (i.e.\ the undelimited one after our string) to the token
% "\expanded@notin". This is an unclosed "\ifx" statement which
% means that this macro behaves similar to a normal \TeX{}
% conditional.
% \begin{macrocode}
\ifx\expanded@notin##2}%
% \end{macrocode}
% After all these preparations we call "\in@@". First we expand the
% token after "\in@@" (which is "\the" from the second argument to
% "\expanded@notin"). As a result we get the contents of the
% "\index@excludelist" inserted after "\in@@". After this contents
% we add once more the string we are looking for, then the token
% "\expanded@notin" and finally the token "\in@@".
% \begin{macrocode}
\expandafter\in@@#2#1\expanded@notin\in@@}
% \end{macrocode}
% Now what happens when the macro "\in@@" above gets called? The
% first argument to "\in@@" is delimited by our string. In other
% words it will get everything from the contents of
% "\index@excludelist" before this string. If the string is not in
% "\index@excludelist" then it gets the whole contents, since after
% it we had inserted the string one more. In this case the next
% token is "\expanded@notin" which gets assigned to the second
% argument and the third argument will be empty. If, on the other
% hand, the string was inside "\index@excludelist" then the second
% argument will not be the token "\expanded@notin" and the third
% argument will be all the garbage up to "\in@@". Therefore testing
% the seconded argument, as done in the definition of "\in@@" will
% tell us whether or not the string is in "\index@includelist" and
% this was exactly what we wanted. (Deep breath.) You got
% that?\footnote{\TeX{}book page 125. The code described above is
% originally due to Michael Spivak who used a similar method within
% the \AmSTeX{} macros.}
% \end{macro}
% \end{macro}
%
%
%
%
%
%
%
% \subsection{Macros for generating index entries}
%
% Here we provide default definitions for the macros invoked to create
% index entries; these are either invoked explicitly, or automatically
% by |\scan@macro|. As already mentioned, the definitions given
% here presuppose that the |.idx| file will be processed by
% Chen's \textsf{makeindex} program --- they may be redefined for use
% with the user's favourite such program.
%
% To assist the reader in locating items in the index, all such
% entries are sorted alphabetically {\em ignoring\/} the initial
% `|\|'; this is achieved by issuing an |\index| command which
% contains the `actual' operator for \textsf{makeindex}. The default
% value for the latter operator is `|@|', but the latter character is
% so popular in \LaTeX\ package files that it is necessary to substitute
% another character. This is indicated to \textsf{makeindex} by means
% of an `index style file'; the character selected for this function
% is |=|, and therefore this character too must be specially treated
% when it is met in a \TeX\ command. A suitable index style file is
% provided amongt the supporting files for this style file in
% \texttt{gind.ist} and is generated from this source by processing
% with \texttt{docstrip} to extract the module \textbf{gind}. A
% similar style file \texttt{gglo.ist} is supplied for sorting the
% change information in the glossary file and is extracted as module
% \textbf{gglo}. First of all we add some information to the front of
% the \texttt{.ist} files. \changes{v1.7a}{1992/03/11}{glo.ist and
% gind.ist now derivable from doc.dtx with docstrip.}
% \begin{macrocode}
%</package>
%<+gind|gglo>%% This is a MAKEINDEX style file which should be used to
%<+gind>%% generate the formatted index for use with the doc
%<+gglo>%% generate the formatted change history for use with the doc
%<+gind|gglo>%% package. The TeX commands used below are defined in
%<+gind|gglo>%% doc.sty. The commands for MAKEINDEX like `level'
%<+gind|gglo>%% `item_x1' are described in `` Makeindex, A General
%<+gind|gglo>%% Purpose, Formatter-Independent Index Processor'' by
%<+gind|gglo>%% Pehong Chen.
%<+gind|gglo>
% \end{macrocode}
%
% \begin{macro}{\actualchar}
% \begin{macro}{\quotechar}
% \begin{macro}{\levelchar}
% First come the definitions of |\actualchar|,
% |\quotechar| and |\levelchar|. Note, that our defaults
% are not the ones used by the \textsf{makeindex} program without a
% style file.
% \begin{macrocode}
%<*package>
\@ifundefined{actualchar}{\def\actualchar{=}}{}
\@ifundefined{quotechar}{\def\quotechar{!}}{}
\@ifundefined{levelchar}{\def\levelchar{>}}{}
%</package>
%<+gind|gglo>actual '='
%<+gind|gglo>quote '!'
%<+gind|gglo>level '>'
%<*package>
% \end{macrocode}
% \end{macro}
% \end{macro}
% \end{macro}
%
%
% \begin{macro}{\encapchar}
% The \textsf{makeindex} default for the |\encapchar| isn't
% changed.
% \begin{macrocode}
\@ifundefined{encapchar}{\def\encapchar{|}}{}
% \end{macrocode}
% \end{macro}
%
%
% \begin{macro}{\verbatimchar}
% We also need a special character to be used as a delimiter for
% the |\verb*| command used in the definitions below.
% \begin{macrocode}
\@ifundefined{verbatimchar}{\def\verbatimchar{+}}{}
% \end{macrocode}
% \end{macro}
%
%
% \begin{macro}{\SpecialIndex}
% The |\SpecialIndex| command creates index entries for
% macros. If the argument is |\|$xyz$, the command produces
% \verb|\indexentry{|$xyz$\verb|=\verb!*+\|$xyz$\verb|+}{|$n$\verb|}|
% given the above defined defaults for |\actualchar|,
% |\quotechar| and |\verbatimchar|. We first remove the
% initial `|\|' to get a better index.
% \changes{v1.5s}{1989/11/05}{Support for code line no. (Undoc)}
% \begin{macrocode}
\def\SpecialIndex#1{\@bsphack\special@index{\expandafter\@gobble
\string#1\actualchar
% \end{macrocode}
% Then follows the actual entry. A |\quotechar| is placed
% before the |*| to allow its use as a special \textsf{makeindex}
% character. Again |\@bsphack| and |\@esphack| are used
% to make the macros invisible.
% \begin{macrocode}
\string\verb\quotechar*\verbatimchar\string#1\verbatimchar}%
\@esphack}
% \end{macrocode}
% \end{macro}
% \begin{macro}{\SpecialMainIndex}
% \begin{macro}{\SpecialMainEnvIndex}
% \begin{macro}{\SpecialUsageIndex}
% The |\SpecialMainIndex| macro is used to cross-reference the
% names introduced by the \textsf{macro} environment. The action is
% as for |\SpecialIndex|, except that \textsf{makeindex} is
% instructed to `encap'sulate the entry with the string
% \verb=|main= to cause it to generate a call of the |\main|
% macro.
% \changes{v1.5s}{1989/11/05}{Support for code line no. (Undoc)}
% \changes{v2.0c}{1998/08/22}{Correctly handle single character
% control sequences like \cs{<}.}
%
% |\SpecialMainIndex| passes the macro name to be indexed on to the
% macro |\SpecialIndex@|.
% \begin{macrocode}
\def\SpecialMainIndex#1{\@bsphack\SpecialIndex@{#1}{\encapchar main}%
\@esphack}
% \end{macrocode}
%
% \begin{macro}{\SpecialIndex@}
% \changes{v2.0c}{1998/08/22}{Macro added.}
% \changes{v2.0f}{1999/02/27}{Temp fix to allow strange code in arg 1
% (PR 2968)}
% The macro |\SpecialIndex@| does the real work for |\SpecialMainIndex|
% and |\SpecialUsageIndex|. It takes two arguments: the macro to be
% indexed (as a control sequence or list of character tokens) and the
% additional text for the index.
% \changes{v2.0g}{1999/03/22}{Correct so-called temp fix. I'm not going to
% explain this.}
% \begin{macrocode}
\begingroup
\catcode`\|=0
\catcode`\\=12
|gdef|@SpecialIndexHelper@#1#2|@nil{%
|if |noexpand#1\%
|gdef|@gtempa{#2}%
|else
|begingroup
|escapechar|m@ne
|expandafter|gdef|expandafter|@gtempa|expandafter{|string#1#2}%
|endgroup
|fi}
|endgroup
\def\SpecialIndex@#1#2{%
% \end{macrocode}
% The first thing it does is to convert the macro into a list of
% characters. Note that a character token list remains (mostly) unchanged.
% \begin{macrocode}
\@SpecialIndexHelper@#1\@nil
% \end{macrocode}
% The macro name \verb*|\ | has to handled in a special way. The reason
% is that the space token is skipped when \TeX\ is scanning macro
% parameters, so that the trick used below will not work.
% So, we check whether the replacement text of |\@tempa| starts with
% a space token and write the appropriate index entry.
% \begin{macrocode}
\def\@tempb{ }%
\ifcat \@tempb\@gtempa
\special@index{\quotechar\space\actualchar
\string\verb\quotechar*\verbatimchar
\quotechar\bslash\quotechar\space\verbatimchar#2}%
\else
% \end{macrocode}
% Having handled this special case we have to distinguish control
% sequences consisting of one or more
% letters and those that consists of exactly one nonletter. As character
% tokens in the replacement text of the macro |\@gtempa| have all
% category code $12$ (other), this is difficult. For simplicity, we treat
% all single character control sequences alike, irregardless of whether
% the character is a letter or not. This has the advantage that it works
% even for strange settings of the category codes.
%
% We define a utility macro |\@tempb| with two arguments, the second
% delimited by |\relax|.
% It will be called later so that the first argument is the first character
% of the macro name, and the second argument receives the rest of the
% characters. So we distinguish the two cases above by checking whether
% the second argument is empty.
% \begin{macrocode}
\def\@tempb##1##2\relax{\ifx\relax##2\relax
% \end{macrocode}
% If so, we define the helper macro |\@tempc| in a way that it
% adds quotechars in critical places.
% \begin{macrocode}
\def\@tempc{\special@index{\quotechar##1\actualchar
\string\verb\quotechar*\verbatimchar
\quotechar\bslash\quotechar##1\verbatimchar#2}}%
% \end{macrocode}
% Otherwise we write the characters as in |\SpecialIndex|.
% \begin{macrocode}
\else
\def\@tempc{\special@index{##1##2\actualchar
\string\verb\quotechar*\verbatimchar
\bslash##1##2\verbatimchar#2}}%
\fi}%
% \end{macrocode}
% Now pass the list of characters to \@tempb and call \@tempc to do the
% work.
% \begin{macrocode}
\expandafter\@tempb\@gtempa\relax
\@tempc
\fi}
% \end{macrocode}
% \end{macro}
%
% Slightly simpler is the main entry for environments
% \changes{v1.9e}{1994/02/03}{use \cs{ttfamily} with \cs{string}}
% \changes{v1.9f}{1994/02/07}{should have used \cs{noexpand}, sigh}
% \changes{v1.9i}{1994/02/11}{should have used \cs{protect}}
% \changes{v1.9j}{1994/02/16}{Back to string:-)}
% \changes{v1.9s}{1994/10/14}{Added missing percent and changed to
% \cs{ttfamily}}
% \changes{v2.0d}{1998/12/20}{Correctly handle second index entry
% by using \cs{special@index} not \cs{index} (PR/2928).}
% \changes{v2.0e}{1998/12/28}{Use \cs{string}, not \cs{protect} in argument to
% \cs{special@index}.}
% \changes{v2.1c}{2004/07/23}{environment names incorrectly sorted in
% index (pr/3615)}
% \begin{macrocode}
\def\SpecialMainEnvIndex#1{\@bsphack\special@index{%
#1\actualchar
{\string\ttfamily\space#1}
(environment)%
\encapchar main}%
\special@index{environments:\levelchar#1\actualchar{%
\string\ttfamily\space#1}\encapchar
main}\@esphack}
% \end{macrocode}
% The |\SpecialUsageIndex| is similar to |\SpecialMainIndex|, except
% that it uses the standard |\index| command.
% \texttt{usage} instead of \texttt{main}.
% \begin{macrocode}
\def\SpecialUsageIndex#1{\@bsphack
{\let\special@index\index\SpecialIndex@{#1}{\encapchar usage}}%
\@esphack}
% \end{macrocode}
% \end{macro}
% \end{macro}
% \end{macro}
%
%
%
%
% \begin{macro}{\SpecialEnvIndex}
% Indexing environments is done a little bit differently; we produce
% two index entries with the |\SpecialEnvIndex| macro:
% \changes{v1.9e}{1994/02/03}{The index needs protecting}
% \changes{v1.9g}{1994/02/08}{should have used \cs{noexpand}, sigh}
% \changes{v1.9i}{1994/02/11}{should have used \cs{protect}}
% \begin{macrocode}
\def\SpecialEnvIndex#1{\@bsphack
% \end{macrocode}
% First we sort the environment under its own name stating in the
% actual entry that this is an environment.
% \begin{macrocode}
\index{#1\actualchar{\protect\ttfamily#1}
(environment)\encapchar usage}%
% \end{macrocode}
% The second entry is sorted as a subitem under the key
% `environments:'.
% \changes{v2.1b}{2004/02/09}{environment names incorrectly sorted in
% index (pr/3615)}
% \begin{macrocode}
\index{environments:\levelchar#1\actualchar
{\protect\ttfamily#1}\encapchar usage}\@esphack}
% \end{macrocode}
% Because both entries correspond to `descriptions' of the
% environment, we encapsulate the page numbers with the
% |\usage| macro.
% \end{macro}
%
%
%
% \begin{macro}{\SortIndex}
% This macro is used to generate the index entries for any
% single-character command that |\scan@macro| encounters. The
% first parameter specifies the lexical order for the character,
% whilst the second gives the actual characters to be printed in
% the entry. It can also be used directly to generate index entries
% which differ in sort key and actual entry.
% \begin{macrocode}
\def\SortIndex#1#2{\index{#1\actualchar#2}}
% \end{macrocode}
% \end{macro}
%
%
%
% \begin{macro}{\it@is@a}
% This macro is supposed to produce a correct |\SortIndex|
% entry for a given character. Since this character might be
% recognised as a `command' character by the index program used,
% all characters are quoted with the |\quotechar|.
% \changes{v1.5s}{1989/11/05}{Support for code line no. (Undoc)}
% \begin{macrocode}
\def\it@is@a#1{\special@index{\quotechar #1\actualchar
\string\verb\quotechar*\verbatimchar
\quotechar\bslash\quotechar#1\verbatimchar}}
% \end{macrocode}
% \end{macro}
%
%
%
% \begin{macro}{\LeftBraceIndex}
% \changes{v1.5s}{1989/11/05}{Support for code line no. (Undoc)}
% \begin{macro}{\RightBraceIndex}
% \changes{v1.5s}{1989/11/05}{Support for code line no. (Undoc)} These
% two macros fix the problems with \textsf{makeindex}. Note the
% `hack' with |\iffalse}\fi| to satisfy both \TeX{} and the
% \textsf{makeindex} program. When this is written to the
% \texttt{.idx} file \TeX{} will see both braces (so we get a
% balanced text). \textsf{makeindex} will also see balanced braces
% but when the actual index entry is again processed by \TeX{} the
% brace in between |\iffalse| |\fi| will vanish.
% \begin{macrocode}
\@ifundefined{LeftBraceIndex}{\def\LeftBraceIndex{%
\special@index{\bgroup\actualchar\string\verb\quotechar*\verbatimchar
\quotechar\bslash{\verbatimchar\string\iffalse}\string\fi}}}{}
\@ifundefined{RightBraceIndex}{\def\RightBraceIndex{%
\special@index{\egroup\actualchar\string\iffalse{\string\fi\string\verb
\quotechar*\verbatimchar\quotechar\bslash}\verbatimchar}}}{}
% \end{macrocode}
% \end{macro}
% \end{macro}
%
%
% \begin{macro}{\PercentIndex}
% \changes{v1.5s}{1989/11/05}{Support for code line no. (Undoc)}
% \changes{v1.7c}{1992/03/25}{Default now for bug-fixed makeindex}
% By default we assume a version of \textsf{makeindex} without the
% percent bug is being used.
% \begin{macrocode}
\@ifundefined{PercentIndex}
{\def\PercentIndex{\it@is@a\percentchar}}{}
% \end{macrocode}
% \end{macro}
% \begin{macro}{\OldMakeindex}
% \changes{v1.7c}{1992/03/26}{Replaced \cs{NewMakeIndex}.}
% \begin{macro}{\percentchar}
% Here is one solution for the percent bug in \textsf{makeindex}.
% The macro |\percentchar| denotes a |%|$_{12}$. Calling this from
% a package or the driver file sets things up
% appropriately.\label{bug:fixes}
% \begin{macrocode}
\def\OldMakeindex{\def\PercentIndex{%
\special@index{\quotechar\percentchar\actualchar\string\verb
\quotechar*\verbatimchar\quotechar\bslash
\percentchar\percentchar\verbatimchar}}}
{\catcode`\%=12 \gdef\percentchar{%}}
% \end{macrocode}
% \end{macro}
% \end{macro}
%
%
%
%
%
%
% \subsection{Redefining the \textsf{index} environment}
%
%\changes{v1.4r}{1989/04/22}{twocols env. placed into separate file}
%\changes{v1.4?}{1989/04/19}{use DEK's algorithm and implement
% a twocols env.}
%\changes{v1.4?}{1989/04/16}{changes to the index env.}
%\changes{v1.5a}{1989/04/26}{Now input multicol.sty instead of
% multcols.sty}
% \begin{macro}{\ifhave@multicol}
% \changes{v1.7a}{1992/03/04}{Added to support avoiding multicol.sty} By
% default the index is set in three columns, and will start on the
% same page as, and underneath, the last part of the text of the
% documented package file, if possible. The last page will be
% reformatted with balanced columns. This requires the
% \textsf{multicols} environment which is described elsewhere. So
% that \DOC{} can be run independently of
% \texttt{multicol.sty} we first check for its existence and set
% the "have@multicol" flag appropriately for use below.
% \changes{v1.9a}{1993/12/02}{Use \cs{IfFileExists}}
% \changes{v1.9m}{1994/04/28}{Use \cs{RequirePackage} to load multicol}
% \begin{macrocode}
\newif\ifhave@multicol
% \end{macrocode}
% If we found \texttt{multicol.sty} we use it. It would be nice to
% delay this (and the re-definition of "theindex") until we knew
% whether an index was actually required \ldots
% \begin{macrocode}
\IfFileExists{multicol.sty}{\have@multicoltrue
\RequirePackage{multicol}%
}{}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\IndexMin}
% \begin{macro}{\c@IndexColumns}
% \changes{v1.4t}{1989/04/24}{Counter added.}
% If \texttt{multicol} is in use,
% when the index is started we compute the remaining space on the
% current page; if it is greater than |\IndexMin|, the first
% part of the index will then be placed in the available space.
% The number of columns set is controlled by the counter
% |\c@IndexColumns| which can be changed with a
% |\setcounter| declaration.
% \begin{macrocode}
\newdimen\IndexMin \IndexMin = 80pt
\newcount\c@IndexColumns \c@IndexColumns = 3
% \end{macrocode}
% \end{macro}
% \end{macro}
%
%
% \begin{environment}{theindex}
% Now we start the multi-column mechanism, if appropriate. We use the
% \LaTeX{} counter |\c@IndexColumns| declared above to denote
% the number of columns and insert the `index prologue' text (which
% might contain a |\section| call, etc.). See the default
% definition for an example.
% \changes{v1.4t}{1989/04/24}{Incorporated new multicols env.}
% \changes{v1.5a}{1989/04/26}{Call multicols first}
% \changes{v1.6e}{1991/04/03}{Turned into env definition.}
% \changes{v1.7a}{1992/03/04}{Include test for multicols.}
% \begin{macrocode}
\ifhave@multicol
\renewenvironment{theindex}
{\begin{multicols}\c@IndexColumns[\index@prologue][\IndexMin]%
% \end{macrocode}
% Then we make a few last minute assignments to read the individual
% index |\item|$\,$s and finish off by ignoring any initial
% space.
% \begin{macrocode}
\IndexParms \let\item\@idxitem \ignorespaces}%
% \end{macrocode}
%
% \begin{macro}{\endtheindex}
% \changes{v1.4t}{1989/04/24}{Incorporated new multicols env.}
% At the end of the index, we have only to end the \textsf{multicols}
% environment.
% \begin{macrocode}
{\end{multicols}}
% \end{macrocode}
% If we can't use \textsf{multicols} we warn the user and use an
% environment that's basically the one from \texttt{article.sty}.
% \begin{macrocode}
\else
\typeout{Can't find multicol.sty -- will use normal index layout if
necessary.}
\def\theindex{\@restonecoltrue\if@twocolumn\@restonecolfalse\fi
\columnseprule \z@ \columnsep 35\p@
\twocolumn[\index@prologue]%
\IndexParms \let\item\@idxitem \ignorespaces}
\def\endtheindex{\if@restonecol\onecolumn\else\clearpage\fi}
\fi
% \end{macrocode}
% \end{macro}
% \end{environment}
%
% Here are the necessary \textsf{makeindex} declarations. We disable
% scanning of macro names inside the index with "\scan@allowedfalse\n"
% to avoid recursion.
% \begin{macrocode}
%</package>
%<+gind>preamble
%<+gind>"\n \\begin{theindex} \n \\makeatletter\\scan@allowedfalse\n"
%<+gind>postamble
%<+gind>"\n\n \\end{theindex}\n"
%<*package>
% \end{macrocode}
%
%
% \begin{macro}{\IndexPrologue}
% \begin{macro}{\index@prologue}
% \changes{v1.9w}{1995/12/27}{Text changed}
% \changes{v1.9x}{1996/01/11}{Text depends on code lines used}
% The |\IndexPrologue| macro is used to place a short message
% into the document above the index. It is implemented by
% redefining |\index@prologue|, a macro which holds the
% default text. We'd better make it a |\long| macro to allow
% |\par| commands in its argument.
% \begin{macrocode}
\long\def\IndexPrologue#1{\@bsphack\def\index@prologue{#1}\@esphack}
% \end{macrocode}
% Now we test whether the default is already defined by another
% package file. If not we define it.
% \changes{v2.0j}{2000/05/22}{Less obscure wording? (CAR pr/3202)}
% \begin{macrocode}
\@ifundefined{index@prologue}
{\def\index@prologue{\section*{Index}%
\markboth{Index}{Index}%
Numbers written in italic refer to the page
where the corresponding entry is described;
numbers underlined refer to the
\ifcodeline@index
code line of the
\fi
definition; numbers in roman refer to the
\ifcodeline@index
code lines
\else
pages
\fi
where the entry is used.
}}{}
% \end{macrocode}
% \end{macro}
% \end{macro}
%
%
%
% \begin{macro}{\IndexParms}
% These are some last-minute assignments for formatting the index
% entries. They are defined in a separate macro so that a user can
% substitute different definitions. We start by defining the
% various parameters controlling leading and the separation between
% the two columns. The entire index is set in |\small| size.
% \begin{macrocode}
\@ifundefined{IndexParms}
{\def\IndexParms{%
\parindent \z@
\columnsep 15pt
\parskip 0pt plus 1pt
\rightskip 15pt
\mathsurround \z@
\parfillskip=-15pt
\small
% \end{macrocode}
% \begin{macro}{\@idxitem}
% \begin{macro}{\subitem}
% \begin{macro}{\subsubitem}
% Index items are formatted with hanging indentation for any items
% which may require more than one line.
% \begin{macrocode}
\def\@idxitem{\par\hangindent 30pt}%
% \end{macrocode}
% Any sub-item in the index is formatted with a 15pt indentation
% under its main heading.
% \begin{macrocode}
\def\subitem{\@idxitem\hspace*{15pt}}%
% \end{macrocode}
% Whilst sub-sub-items go in a further 10pt.
% \begin{macrocode}
\def\subsubitem{\@idxitem\hspace*{25pt}}%
% \end{macrocode}
% \begin{macro}{\indexspace}
% The \textsf{makeindex} program generates an |\indexspace|
% before each new alphabetic section commences. After this final
% definition we end the |\@ifundefined| and the definition of
% |\IndexParms|.
% \begin{macrocode}
\def\indexspace{\par\vspace{10pt plus 2pt minus 3pt}}%
}}{}
% \end{macrocode}
% \end{macro}
% \end{macro}
% \end{macro}
% \end{macro}
% \end{macro}
%
%
% \begin{macro}{\efill}
% This definition of |\efill| is intended to be used after index
% items which have no following text (for example, ``\textit{
% see\/}'' entries). It just ensures that the current line is
% filled, preventing ``|Underfull \hbox|'' messages.
% \begin{macrocode}
\def\efill{\hfill\nopagebreak}%
%</package>
%<+gind|gglo>item_x1 "\\efill \n \\subitem "
%<+gglo>item_x2 "\\ "
%<+gind>item_x2 "\\efill \n \\subsubitem "
%<*package>
% \end{macrocode}
% \end{macro}
%
%
%
% \begin{macro}{\pfill}
% \begin{macro}{\dotfil}
% \begin{macro}{\dotfill}
% The following definitions provide the |\pfill| command; if
% this is specified in the index style file to \textsf{makeindex} as
% the delimiter to appear after index items, then the intervening
% space before the referenced page numbers will be filled with
% dots, with a little white space interpolated at each end of the
% dots. If the line is broken the dots will show up on both lines.
% \changes{v2.1i}{2018/09/25}{Guard against following \cs{unskip} (git/23)}
% \begin{macrocode}
\def\dotfill{\leaders\hbox to.6em{\hss .\hss}\hskip\z@ plus 1fill\kern\z@}%
\def\dotfil{\leaders\hbox to.6em{\hss .\hss}\hfil\kern\z@}%
\def\pfill{\unskip~\dotfill\penalty500\strut\nobreak
\dotfil~\ignorespaces}%
%</package>
%<+gind|gglo>delim_0 "\\pfill "
%<+gind|gglo>delim_1 "\\pfill "
%<+gind|gglo>delim_2 "\\pfill "
%<*package>
% \end{macrocode}
% \end{macro}
% \end{macro}
% \end{macro}
%
%
%
% \begin{macro}{\*}
% Here is the definition for the |\*| macro. It isn't used in
% this set of macros.
% \begin{macrocode}
\def\*{\leavevmode\lower.8ex\hbox{$\,\widetilde{\ }\,$}}
% \end{macrocode}
% \end{macro}
%
%
% \begin{macro}{\main}
% The \textit{defining\/} entry for a macro name is flagged with
% the string \texttt{\encapchar main}\footnote{With the current
% definition of \texttt{\bslash encapchar} substituted for
% \texttt{\encapchar}} in the |\index| command; \textsf{makeindex}
% processes this so that the |\main| macro will be invoked to
% underline the page number(s) on which the {\em definition\/} of
% the macro will be found.
% \begin{macrocode}
\@ifundefined{main}{\def\main#1{\underline{#1}}}{}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\usage}
% The |\usage| macro is used to indicate entries describing
% the usage of a macro. The corresponding page number(s) will be
% set in \textit{italics}.
% \begin{macrocode}
\@ifundefined{usage}{\def\usage#1{\textit{#1}}}{}
% \end{macrocode}
% \end{macro}
%
%
% \begin{macro}{\PrintIndex}
% \changes{v1.5k}{1989/09/04}{\cs{printindex} changed to
% \cs{PrintIndex}}
% \changes{v1.7a}{1992/02/26}{Documentation moved to interface section.}
% \changes{v1.9h}{1994/02/10}{Use \cs{@input@} instead of \cs{@input}.}
% \changes{v1.9w}{1995/12/29}{Turn the cmd into a noop after use.}
% This is the same as "\printindex" in the \textsf{makeidx} package.
% \begin{macrocode}
\def\PrintIndex{\@input@{\jobname.ind}%
\global\let\PrintIndex\@empty}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\printindex}
% Since the above macro was called |\printindex| in older versions
% of \texttt{doc.sty} the following definition was provided up to
% version 1.9y.
% \changes{v1.9z}{1996/04/17}{Commented out}
% \begin{macrocode}
%\def\printindex{\typeout{\string\printindex\space is obsolete!}%
% \typeout{Please use \string\PrintIndex\space
% if you are a macro implementor^^J
% or get a newer version of the documented
% software if you are a user}%
% \PrintIndex}
% \end{macrocode}
% \end{macro}
%
% We want headings in the index (and changes list) according to the
% initial character of the next block of entries and have to instruct
% \textsf{makeindex} appropriately. Unfortunately the specification
% for this changed sometime between versions 2.4 and 2.11 of
% \textsf{makeindex}. We provide both ways of doing it but
% unfortunately this will always produce a warning message from
% \textsf{makeindex}. This is for older versions:
% \changes{v1.7h}{1992/07/01}{Turn off headings in gls file}
% \begin{macrocode}
%</package>
%<+gind,gglo>% The next lines will produce some warnings when
%<+gind,gglo>% running Makeindex as they try to cover two different
%<+gind,gglo>% versions of the program:
%<+gind,gglo>lethead_prefix "{\\bfseries\\hfil "
%<+gind,gglo>lethead_suffix "\\hfil}\\nopagebreak\n"
%<+gind>lethead_flag 1
%<+gglo>lethead_flag 0
% \end{macrocode}
% This works for newer ones:
% \begin{macrocode}
%<+gind,gglo>heading_prefix "{\\bfseries\\hfil "
%<+gind,gglo>heading_suffix "\\hfil}\\nopagebreak\n"
%<+gind>headings_flag 1
%<+gglo>headings_flag 0
%<*package>
% \end{macrocode}
%
%
%
% \subsection[Dealing with the change history]
% {Dealing with the change history\footnotemark}
% \footnotetext{The whole section was proposed by Brian \textsc{Hamilton
% Kelly}. He also documented and debugged the macros as
% well as many other parts of this package.}
%
% To provide a change history log, the |\changes| command has
% been introduced. This takes three arguments, respectively, the
% version number of the file, the date of the change, and some detail
% regarding what change has been made. The second of these arguments
% is otherwise ignored, but the others are written out and may be used
% to generate a history of changes, to be printed at the end of the
% document. However, note that older versions of Chen's standard
% \textsf{makeindex}
% program limit any textual field to just 64 characters; therefore,
% is important that the number of characters in the second and third
% parameters should not exceed 61 altogether (to allow for the
% parentheses placed around the date).
%
% \begin{macro}{\changes}
% \changes{BHK}{1989/04/26}{Documented \texttt{\protect\bslash changes}
% command.}
% \changes{BHK}{1989/04/26}{Changed definition of
% \texttt{\protect\bslash protect}.} The output of the |\changes|
% command goes into the \meta{Glossary\_File} and therefore uses
% the normal |\glossaryentry| commands.\footnote{Note that a recent
% change in \LaTeX{} 2.09 changed the command name in the
% \texttt{.glo} file from \texttt{\bslash indexentry} to
% \texttt{\bslash glossaryentry}. It is therefore necessary to
% have a special \textsf{makeindex} style file called
% \texttt{gglo.ist} to process this file correctly.} Thus
% \textsf{makeindex} or a similar program can be used to process
% the output into a sorted ``glossary''. The |\changes| command
% commences by taking the usual measures to hide its spacing, and
% then redefines |\protect| for use within the argument of the
% generated |\indexentry| command.
%
% We re-code nearly all chars found in |\sanitize| to letter
% since the use of special package which make some characters
% active might upset the |\changes| command when writing its
% entries to the file. However we have to leave |%| as comment
% and \verb*+ + as \meta{space} otherwise chaos will happen.
% And, of course the |\| should be available as escape
% character.
% \changes{v1.5v}{1990/01/28}{`Re-code a lot of chars.}
% \changes{v1.5m}{1989/09/20}{\cs{actualchar} in second level removed.}
% \changes{v1.5o}{1989/09/24}{New sorting.}
% \changes{v1.6c}{1990/06/29}{Again new sorting.}
% \changes{v1.9u}{1995/08/06}{Use \cs{protected@edef}}
% \begin{macrocode}
\def\changes{\@bsphack\begingroup\@sanitize
\catcode`\\\z@ \catcode`\ 10 \MakePercentIgnore
\changes@}
\def\changes@#1#2#3{%
\protected@edef\@tempa{\noexpand\glossary{#1\levelchar
% \end{macrocode}
% \changes{v1.9u}{1995/08/06}{Use value of \cs{saved@macroname} to
% find out about change entries at outer level}
% If the macro "\saved@macroname" doesn't contain any macro name
% (ie is empty) the current changes entry was done at top-level.
% In this case we precede it by "\generalname".
% \begin{macrocode}
\ifx\saved@macroname\@empty
\space
\actualchar
\generalname
\else
% \end{macrocode}
% \changes{v2.1g}{2016/02/15}{Use \cs{saved@indexname}}
% \begin{macrocode}
\saved@indexname
\actualchar
\string\verb\quotechar*%
\verbatimchar\saved@macroname
\verbatimchar
\fi
:\levelchar #3}}%
\@tempa\endgroup\@esphack}
% \end{macrocode}
%
% \begin{macro}{\saved@macroname}
% \changes{BHK}{1989/04/26}{Provided for sorting outside \textsf{macro}
% environment} The entries are sorted for convenience by the name
% of the most recently introduced macroname (i.e., that in the most
% recent |\begin{macro}| command). We therefore provide
% |\saved@macroname| to record that argument, and provide a default
% definition in case |\changes| is used outside a \textsf{macro}
% environment. (This is a {\em wicked\/} hack to get such entries
% at the beginning of the sorted list! It works providing no macro
% names start with "!" or |"|.) \changes{v1.7a}{1992/03/02}{Changed
% string used for better sorting.}
% \changes{v1.9u}{1995/08/06}{Now empty by default}
% \begin{macrocode}
\def\saved@macroname{}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\saved@indexname}
% \changes{v2.1g}{2016/02/15}{Use \cs{saved@indexname}}
% The macroname being document without a backslash for the index
% (or the environment name which doesn't have one in the first place).
% \begin{macrocode}
\def\saved@indexname{}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\generalname}
% \changes{v1.9u}{1995/08/06}{Macro added}
% This macro holds the string placed before changes entries on
% top-level.
% \begin{macrocode}
\def\generalname{General}
% \end{macrocode}
% \end{macro}
%
%
% \begin{macro}{\RecordChanges}
% \changes{BHK}{1989/04/26}{Renames former \texttt{\protect\bslash
% PrintChanges} command.}
% To cause the changes to be written (to a \texttt{.glo}) file, we
% define |\RecordChanges| to invoke \LaTeX's usual
% |\makeglossary| command.
% \begin{macrocode}
\let\RecordChanges\makeglossary
% \end{macrocode}
% \end{macro}
% \end{macro}
%
%
% \begin{macro}{\GlossaryMin}
% \changes{BHK}{1989/04/26}{Added to support
% \texttt{\protect\bslash changes}.}
% \begin{macro}{\c@GlossaryColumns}
% \changes{BHK}{1989/04/26}{Added to support \texttt{\protect\bslash
% changes}.} The remaining macros are all analogues of those used
% for the \textsf{theindex} environment. When the glossary is
% started we compute the space which remains at the bottom of the
% current page; if this is greater than |\GlossaryMin| then the
% first part of the glossary will be placed in the available space.
% The number of columns set are controlled by the counter
% |\c@GlossaryColumns| which can be changed with a |\setcounter|
% declaration.
% \begin{macrocode}
\newdimen\GlossaryMin \GlossaryMin = 80pt
\newcount\c@GlossaryColumns \c@GlossaryColumns = 2
% \end{macrocode}
% \end{macro}
% \end{macro}
%
%
% \begin{environment}{theglossary}
% \changes{BHK}{1989/04/26}{Added to support
% \texttt{\protect\bslash changes}.}
% \changes{v1.5p}{1989/09/28}{Now call \cs{multicols} first.}
% \changes{v1.6e}{1991/04/03}{Turned into env definition.}
% \changes{v1.7a}{1992/03/10}{Changed to work without multicols if
% necessary.}
% \begin{macro}{\endglossary}
% \changes{BHK}{1989/04/26}{Added to support
% \texttt{\protect\bslash changes}.}
% The environment \textsf{theglossary} is defined in the same manner
% as the \textsf{theindex} environment.
% \begin{macrocode}
\ifhave@multicol
\newenvironment{theglossary}{%
\begin{multicols}\c@GlossaryColumns
[\glossary@prologue][\GlossaryMin]%
\GlossaryParms \let\item\@idxitem \ignorespaces}%
{\end{multicols}}
\else
\newenvironment{theglossary}{%
\@restonecoltrue\if@twocolumn\@restonecolfalse\fi
\columnseprule \z@ \columnsep 35\p@
\twocolumn[\glossary@prologue]%
\GlossaryParms \let\item\@idxitem \ignorespaces}
{\if@restonecol\onecolumn\else\clearpage\fi}
\fi
% \end{macrocode}
% \end{macro}
% \end{environment}
%
% Here are the necessary \textsf{makeindex} declarations with scanning
% disabled as for the index.
% \begin{macrocode}
%</package>
%<+gglo>preamble
%<+gglo>"\n \\begin{theglossary} \n
%<+gglo> \\makeatletter\\scan@allowedfalse\n"
%<+gglo>postamble
%<+gglo>"\n\n \\end{theglossary}\n"
% \end{macrocode}
% This difference from \texttt{gind.ist} is necessary if you have an
% up-to-date \LaTeX.
% \begin{macrocode}
%<+gglo>keyword "\\glossaryentry"
%<*package>
% \end{macrocode}
%
%
% \begin{macro}{\GlossaryPrologue}
% \changes{BHK}{1989/04/26}{Added to support
% \texttt{\protect\bslash changes}.}
% \begin{macro}{\glossary@prologue}
% \changes{BHK}{1989/04/26}{Added to support
% \texttt{\protect\bslash changes}.}
% The |\GlossaryPrologue| macro is used to place a short
% message above the glossary into the document. It is implemented
% by redefining |\glossary@prologue|, a macro which holds the
% default text. We better make it a long macro to allow
% |\par| commands in its argument.
% \begin{macrocode}
\long\def\GlossaryPrologue#1{\@bsphack
\def\glossary@prologue{#1}%
\@esphack}
% \end{macrocode}
% Now we test whether the default is already defined by another
% package file. If not we define it.
% \begin{macrocode}
\@ifundefined{glossary@prologue}
{\def\glossary@prologue{\section*{{Change History}}%
\markboth{{Change History}}{{Change History}}%
}}{}
% \end{macrocode}
% \end{macro}
% \end{macro}
%
% \begin{macro}{\GlossaryParms}
% \changes{BHK}{1989/04/26}{Added to support
% \texttt{\protect\bslash changes}.}
% Unless the user specifies otherwise, we set the change history
% using the same parameters as for the index except that we make it sort
% of ragged right as it contains text that often doesn't break nicely in
% small columns.
% \changes{v2.1g}{2016/02/15}{Use ragged setting by default}
% \begin{macrocode}
\@ifundefined{GlossaryParms}{\let\GlossaryParms\IndexParms
\expandafter\def\expandafter\GlossaryParms\expandafter{\GlossaryParms
\rightskip 15pt plus 1fil
\parfillskip -15pt plus -1fil\relax}
}{}
% \end{macrocode}
% \end{macro}
% \begin{macro}{\PrintChanges}
% \changes{BHK}{1989/04/26}{Added to support
% \texttt{\protect\bslash changes}.}
% To read in and print the sorted change history, just put the
% |\PrintChanges| command as the last (commented-out, and thus
% executed during the documentation pass through the file) command
% in your package file. Alternatively, this command may form one of
% the arguments of the |\StopEventually| command, although a
% change history is probably {\em not\/} required if only the
% description is being printed.
%
% The command assumes that \textsf{makeindex} or some other program
% has processed the \texttt{.glo} file to generate a sorted
% \texttt{.gls} file.
% \changes{v1.9h}{1994/02/10}{Use \cs{@input@} instead of \cs{@input}.}
% \changes{v1.9w}{1995/12/29}{Turn the cmd into a noop after use.}
% \begin{macrocode}
\def\PrintChanges{\@input@{\jobname.gls}%
\global\let\PrintChanges\@empty}
% \end{macrocode}
% \end{macro}
%
%
%
%
%
% \subsection{Bells and whistles}
%
% \begin{macro}{\StopEventually}
% \changes{v1.5k}{1989/09/04}{Support for checksum.}
% \begin{macro}{\Finale}
% \changes{v1.5k}{1989/09/04}{Support for checksum.}
% \changes{v1.5z}{1990/04/22}{Define \cs{Finale} globally.}
% \begin{macro}{\AlsoImplementation}
% \changes{v1.9w}{1995/12/27}{Macro added}
% \begin{macro}{\OnlyDescription}
% If |\AlsoImplementation| is in force the whole documentation
% including the code part will be typeset. This is the default.
% \begin{macrocode}
\newcommand\AlsoImplementation{%
% \end{macrocode}
% To make this happen we have to define
% |\StopEventually| in a way that its argument is typeset at the
% very end or more exactly at |\Finale|. For this we
% save its argument in the macro |\Finale|.
% \begin{macrocode}
\long\def\StopEventually##1{\@bsphack\gdef\Finale{##1%
% \end{macrocode}
% But |\Finale| will be called at the very end of a file. This
% is exactly the point were we want to know if the file is
% uncorrupted. Therefore we also call |\check@checksum| at this
% point.
% \begin{macrocode}
\check@checksum}%
% \end{macrocode}
% On the other hand: |\StopEventually| is more or less a
% dividing point between description and code. So we start to look
% for the check-sum of the documented file by calling
% |\init@checksum|.
% \begin{macrocode}
\init@checksum
\@esphack}%
}
% \end{macrocode}
%
% Since |\AlsoImplementation| should be the default we execute it
% and thus |\StopEventually| gets the desired meaning.
% \begin{macrocode}
\AlsoImplementation
% \end{macrocode}
% When the user places an |\OnlyDescription| declaration in
% the driver file the document should only be typeset up to
% |\StopEventually|. We therefore have to redefine this macro.
% \begin{macrocode}
\def\OnlyDescription{\@bsphack\long\def\StopEventually##1{%
% \end{macrocode}
% In this case the argument of |\StopEventually| should be set
% and afterwards \TeX{} should stop reading from this file.
% Therefore we finish this macro with
% \begin{macrocode}
##1\endinput}\@esphack}
% \end{macrocode}
% If no |\StopEventually| command is given we silently ignore a
% |\Finale| issued.
% \changes{v1.9n}{1994/04/28}{Ignore \cs{Finale} if no
% \cs{StopEventually} is given}
% \begin{macrocode}
\let\Finale\relax
% \end{macrocode}
% \end{macro}
% \end{macro}
% \end{macro}
% \end{macro}
%
% \begin{macro}{\meta}
% \changes{v1.4t}{1989/04/24}{Macro added.}
% \changes{v1.5w}{1990/02/03}{Breaks at space allowed.}
% \changes{v1.6a}{1990/05/24}{Extra space bug corrected.}
% The |\meta| macro is a bit tricky. We want to allow line
% breaks at blanks in the argument but we don't want a break
% in between. In the past this was done by defining |\meta| in a way that a
% \verb*+ + is active when the argument is scanned. Words are then
% scanned into |\hbox|es. The active \verb*+ + will end the
% preceding |\hbox| add an ordinary space and open a new
% |\hbox|. In this way breaks are only possible at spaces. The
% disadvantage of this method was that |\meta| was neither robust
% nor could it be |\protect|ed. The new implementation fixes this
% problem by defining |\meta| in a radically different way: we
% prevent hyphenation by defining a |\language| which has no
% patterns associated with it and use this to typeset the words
% within the angle brackets.
% \changes{v2.0i}{2000/05/21}{New implementation (pr/3170)}
% \begin{macrocode}
\ifx\l@nohyphenation\undefined
\newlanguage\l@nohyphenation
\fi
% \end{macrocode}
%
% \begin{macrocode}
\DeclareRobustCommand\meta[1]{%
% \end{macrocode}
% Since the old implementation of |\meta| could be used in math we
% better ensure that this is possible with the new one as
% well. So we use |\ensuremath| around |\langle| and
% |\rangle|. However this is not enough: if |\meta@font@select|
% below expands to |\itshape| it will fail if used in math
% mode. For this reason we hide the whole thing inside an
% |\nfss@text| box in that case.
% \changes{v2.0l}{2000/06/10}{Fixing changes for (pr/3170)}
% \begin{macrocode}
\ensuremath\langle
\ifmmode \expandafter \nfss@text \fi
{%
\meta@font@select
% \end{macrocode}
% Need to keep track of what we changed just in case the user
% changes font inside the argument so we store the font explicitly.
% \changes{v2.0m}{2000/07/04}{More fixing changes for (pr/3170)}
% \begin{macrocode}
\edef\meta@hyphen@restore
{\hyphenchar\the\font\the\hyphenchar\font}%
\hyphenchar\font\m@ne
\language\l@nohyphenation
#1\/%
\meta@hyphen@restore
}\ensuremath\rangle
}
% \end{macrocode}
% \end{macro}
%
%
% \begin{macro}{\meta@font@select}
% \changes{v2.0k}{2000/05/26}{Macro added (pr/3170)}
% Make font used inside |\meta| customizable.
% \begin{macrocode}
\def\meta@font@select{\itshape}
% \end{macrocode}
% \end{macro}
%
%
% \begin{macro}{\IndexInput}
% This next macro may be used to read in a separate file (possibly
% a package file that is {\em not\/} documented by this means) and
% set it verbatim, whilst scanning for macro names and indexing the
% latter. This could be a useful first pass in preparing to
% generate documentation for the file read.
% \begin{macrocode}
\def\IndexInput#1{%
% \end{macrocode}
% We commence by setting up a group, and initializing a
% |\trivlist| as is normally done by a
% |\begin{macrocode}| command.
% \begin{macrocode}
\begingroup \macro@code
% \end{macrocode}
% We also make spacing behave as in the \textsf{macrocode}
% environment, because otherwise all the spaces will be shown
% explicitly.
% \begin{macrocode}
\frenchspacing \@vobeyspaces
% \end{macrocode}
% Then it only remains to read in the specified file, and finish
% off the |\trivlist|.
% \changes{v1.5t}{1989/11/07}{Call \cs{endmacrocode} instead
% of \cs{endtrivlist}.}
% \begin{macrocode}
\input{#1}\endmacrocode
% \end{macrocode}
% Of course, we need to finish off the group as well.
% \begin{macrocode}
\endgroup}
% \end{macrocode}
% \end{macro}
%
%
% \begin{macro}{\maketitle}
% The macro to generate titles is easily altered in order that it
% can be used more than once (an article with many titles). In the
% original, diverse macros were concealed after use with
% |\relax|. We must cancel anything that may have been put
% into |\@thanks|, etc., otherwise {\em all\/} titles will
% carry forward any earlier such setting!
% \changes{v1.5j}{1989/06/09}{thispagestyle plain removed}
% \changes{v1.9r}{1994/06/09}{Added new definitions of
% \cs{@makefnmark} and \cs{@makefntext}}
% \begin{macrocode}
\def\maketitle{\par
\begingroup \def \thefootnote {\fnsymbol {footnote}}%
\setcounter {footnote}\z@
\def\@makefnmark{\hbox to\z@{$\m@th^{\@thefnmark}$\hss}}%
\long\def\@makefntext##1{\parindent 1em\noindent
\hbox to1.8em{\hss$\m@th^{\@thefnmark}$}##1}%
\if@twocolumn \twocolumn [\@maketitle ]%
\else \newpage \global \@topnum \z@ \@maketitle \fi
% \end{macrocode}
% \changes{v1.5k}{1989/09/04}{Added \cs{ps@titlepage}}
% For special formatting requirements (such as in TUGboat), we use
% pagestyle |titlepage| for this; this is later defined to be
% |plain|, unless already defined, as, for example, by
% |ltugboat.sty|.
% \begin{macrocode}
\thispagestyle{titlepage}\@thanks \endgroup
% \end{macrocode}
% If the driver file documents many files, we don't want parts of a
% title of one to propagate to the next, so we have to cancel
% these:
% \begin{macrocode}
\setcounter {footnote}\z@
\gdef\@date{\today}\gdef\@thanks{}%
\gdef\@author{}\gdef\@title{}}
% \end{macrocode}
% \end{macro}
%
%
% \begin{macro}{\ps@titlepage}
% \changes{v1.5k}{1989/09/04}{Added \texttt{\protect\bslash
% ps@titlepage}} When a number of articles are concatenated into a
% journal, for example, it is not usual for the title pages of such
% documents to be formatted differently. Therefore, a class
% such as \textsf{ltugboat} can define this macro in advance.
% However, if no such definition exists, we use pagestyle
% \texttt{plain} for title pages.
% \begin{macrocode}
\@ifundefined{ps@titlepage}
{\let\ps@titlepage=\ps@plain}{}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\MakeShortVerb}
% \changes{v1.7a}{1992/02/27}{Added (from newdoc but now alters
% \cs{dospecials}, \cs{@sanitize}).}
% This arranges an abbreviation for "\verb" such that if you say
% "\MakeShortVerb{\"\meta{c}"}" subsequently using
% \meta{c}\meta{text}\meta{c} is equivalent to
% "\verb"\meta{c}\meta{text}\meta{c}.\footnote{Warning:
% the commentary in the rest of this section was written by Dave
% Love.} In addition, the fact
% that \meta{c} is made active is recorded for the benefit of the
% \textsf{verbatim} and \textsf{macrocode} environments.
% Note particularly that the definitions below are global.
% The first thing we do (it needn't be first) is to record
% the---presumably new---special character in "\dospecials" and
% "\@sanitize" using "\add@special".
%
% \changes{v1.9e.2}{1994/02/07}{-js: Check if \protect\meta{c} is
% already an
% abbreviation for \cs{verb}.}
% Some unwary user might issue "\MakeShortVerb" for a second time, we
% better protect against this. We assume that this happened if a
% control sequence "\cc\"\meta{c} is bound, the probability that this
% name is used by another module is low. We will output a warning
% below, so that a possible error might be noticed by the programmer
% if he reads the "LOG" file. (Should have used module internal names,
% 'though.)
%
% \begin{macro}{\MakeShortVerb*}
% \changes{v2.1a}{2003/12/09}{(HjG) Added \texttt{*} form}
% This arranges an abbreviation for "\verb*" such that if you say
% "\MakeShortVerb*{\"\meta{c}"}" subsequently using
% \meta{c}\meta{text}\meta{c} is equivalent to
% "\verb*"\meta{c}\meta{text}\meta{c}.
% \begin{macrocode}
%</package>
%<*package|shortvrb>
\def\MakeShortVerb{%
\@ifstar
{\def\@shortvrbdef{\verb*}\@MakeShortVerb}%
{\def\@shortvrbdef{\verb}\@MakeShortVerb}}
% \end{macrocode}
% \end{macro}
% \begin{macrocode}
\def\@MakeShortVerb#1{%
\expandafter\ifx\csname cc\string#1\endcsname\relax
% \end{macrocode}
% \changes{v1.9v}{1995/11/03}{(DPC) Use \cs{@shortvrbinfo}}
% \begin{macrocode}
\@shortvrbinfo{Made }{#1}\@shortvrbdef
\add@special{#1}%
% \end{macrocode}
% Then the character's current catcode is stored in "\cc\"\meta{c}.
% \begin{macrocode}
\expandafter
\xdef\csname cc\string#1\endcsname{\the\catcode`#1}%
% \end{macrocode}
% The character is spliced into the definition using the same trick as
% used in "\verb" (for instance), having activated "~" in a group.
% \begin{macrocode}
\begingroup
\catcode`\~\active \lccode`\~`#1%
\lowercase{%
% \end{macrocode}
% The character's old meaning is recorded in "\ac\"\meta{c} prior to
% assigning it a new one.
% \begin{macrocode}
\global\expandafter\let
\csname ac\string#1\endcsname~%
\expandafter\gdef\expandafter~\expandafter{\@shortvrbdef~}}%
\endgroup
% \end{macrocode}
% Finally the character is made active.
% \begin{macrocode}
\global\catcode`#1\active
% \end{macrocode}
% If we suspect that \meta{c} is already a short reference, we tell
% the user. Now he or she is responsible if anything goes wrong\,\dots
% \begin{macrocode}
\else
% \end{macrocode}
% \changes{v1.9v}{1995/11/03}{(DPC) Use \cs{@shortvrbinfo}}
% \begin{macrocode}
\@shortvrbinfo\@empty{#1 already}{\@empty\verb(*)}%
\fi}
% \end{macrocode}
% \end{macro}
% \begin{macro}{\DeleteShortVerb}
% \changes{v1.7a}{1992/02/27}{Added (from newdoc but now alters
% \cs{dospecials}, \cs{@sanitize}).}
% Here's the means of undoing a "\MakeShortVerb", for instance in a
% region where you need to use the character outside a verbatim
% environment. It arranges for "\dospecials" and "\@sanitize" to be
% altered appropriately, restores the saved catcode and, if necessary,
% the character's meaning (as stored by
% "\MakeShortVerb"). If the catcode wasn't stored in
% "\cc\"\meta{c} (by "\MakeShortVerb") the command is silently
% ignored.
% \changes{v1.7a}{1992/02/28}{Check for previous matched
% \cs{MakeShortVerb}
% to avoid error.}
% \begin{macrocode}
\def\DeleteShortVerb#1{%
\expandafter\ifx\csname cc\string#1\endcsname\relax
% \end{macrocode}
% \changes{v2.1a}{2003/12/10}{(HjG) Notify user
% if it's not a short verb character}
% \begin{macrocode}
\@shortvrbinfo\@empty{#1 not}{\@empty\verb(*)}%
\else
% \end{macrocode}
% \changes{v1.9v}{1995/11/03}{(DPC) Use \cs{@shortvrbinfo}}
% \begin{macrocode}
\@shortvrbinfo{Deleted }{#1 as}{\@empty\verb(*)}%
\rem@special{#1}%
\global\catcode`#1\csname cc\string#1\endcsname
% \end{macrocode}
% \changes{v1.9e.2}{1994/02/07}{-js: Reset `cc`\protect\meta{c} in
% \cs{DeleteShortVerb}}
% We must not forget to reset "\cc\"\meta{c}, otherwise the check in
% "\MakeShortVerb" for a repeated definition will not work.
% \begin{macrocode}
\global \expandafter\let \csname cc\string#1\endcsname \relax
\ifnum\catcode`#1=\active
\begingroup
\catcode`\~\active \lccode`\~`#1%
\lowercase{%
\global\expandafter\let\expandafter~%
\csname ac\string#1\endcsname}%
\endgroup \fi \fi}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\@shortvrbinfo}
% \changes{v1.9v}{1995/11/03}{(DPC) Macro added}
% \changes{v2.1a}{2003/12/10}{(HjG) Third argument added
% on behalf of \cmd{\MakeShortVerb*}}
% Helper function for info messages.
% \begin{macrocode}
\def\@shortvrbinfo#1#2#3{%
%<shortvrb> \PackageInfo{shortvrb}{%
%<!shortvrb> \PackageInfo{doc}{%
#1\expandafter\@gobble\string#2 a short reference
for \expandafter\string#3}}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\add@special}
% \changes{v1.7a}{1992/02/27}{Added for short verb facility.}
% This helper macro adds its argument to the
% "\dospecials" macro which is conventionally used by verbatim macros
% to alter the catcodes of the currently active characters. We need
% to add "\do\"\meta{c} to the expansion of "\dospecials" after
% removing the character if it was already there to avoid multiple
% copies building up should "\MakeShortVerb" not be balanced by
% "\DeleteShortVerb" (in case anything that uses "\dospecials" cares
% about repetitions).
% \begin{macrocode}
\def\add@special#1{%
\rem@special{#1}%
\expandafter\gdef\expandafter\dospecials\expandafter
{\dospecials \do #1}%
% \end{macrocode}
% Similarly we have to add "\@makeother\"\meta{c} to "\@sanitize"
% (which is used in things like "\index" to re-catcode all special
% characters except braces).
% \begin{macrocode}
\expandafter\gdef\expandafter\@sanitize\expandafter
{\@sanitize \@makeother #1}}
% \end{macrocode}
% \end{macro}
% \begin{macro}{\rem@special}
% \changes{v1.7a}{1992/02/27}{Added for short verb facility.}
% The inverse of "\add@special" is slightly trickier. "\do" is
% re-defined to expand to nothing if its argument is the character of
% interest, otherwise to expand simply to the argument. We can then
% re-define "\dospecials" to be the expansion of itself. The space
% after "=`##1" prevents an expansion to "\relax"!
% \begin{macrocode}
\def\rem@special#1{%
\def\do##1{%
\ifnum`#1=`##1 \else \noexpand\do\noexpand##1\fi}%
\xdef\dospecials{\dospecials}%
% \end{macrocode}
% Fixing "\@sanitize" is the same except that we need to re-define
% "\@makeother" which obviously needs to be done in a group.
% \begin{macrocode}
\begingroup
\def\@makeother##1{%
\ifnum`#1=`##1 \else \noexpand\@makeother\noexpand##1\fi}%
\xdef\@sanitize{\@sanitize}%
\endgroup}
%</package|shortvrb>
%<*package>
% \end{macrocode}
% \end{macro}
% \begin{macro}{\MakeShortverb}
% \begin{macro}{\DeleteShortverb}
% \changes{v1.7a}{1992/02/27}{Added (from newdoc).}
% These commands from \textsf{newdoc} are now obsolete.
% \begin{macrocode}
\def\MakeShortverb{\typeout{*** Switch to \noexpand\MakeShortVerb
syntax, this is obsolete ***}\MakeShortVerb}
\def\DeleteShortverb{\typeout{*** Switch to \noexpand\DeleteShortVerb
syntax, this is obsolete ***}\DeleteShortVerb}
% \end{macrocode}
% \end{macro}
% \end{macro}
%
%
%
% \subsection[Providing a checksum and character table]
% {Providing a checksum and character table\footnotemark}
% \footnotetext{Warning: the commentary in this section was
% written by Dave Love. }
%
%
% \begin{macro}{\init@checksum}
% The checksum mechanism works by counting backslashes in the
% macrocode. This initializes the count (when called from
% "\StopEventually").
% \changes{v1.5k}{1989/09/04}{Macro added to support checksum.}
% \begin{macrocode}
\def\init@checksum{\relax
\global\bslash@cnt\z@}
% \end{macrocode}
% \end{macro}
%
%
% \begin{macro}{\check@checksum}
% \changes{v1.5k}{1989/09/04}{Macro added to support checksum.}
% This reports the sum compared with the value ("\bslash@cnt") the
% file advertises. It's called from "\Finale" (if that hasn't been
% re-defined).
% \changes{v2.1f}{2016/02/12}{Suppress \cs{CheckSum} check if no checksum
% is specified in the file}
% \begin{macrocode}
\def\check@checksum{\relax
\ifnum\check@sum>\m@ne
% \end{macrocode}
% We do nothing if the checksum in the file is negative (or not given as
% it is initialized with -1).
% \begin{macrocode}
\ifnum\check@sum=\z@
\typeout{**********************************}%
\typeout{* This macro file has no checksum!}%
\typeout{* The checksum should be \the\bslash@cnt!}%
\typeout{**********************************}%
\else
\ifnum\check@sum=\bslash@cnt
\typeout{*******************}%
\typeout{* Checksum passed *}%
\typeout{*******************}%
\else
\PackageError{doc}{Checksum not passed
(\the\check@sum<>\the\bslash@cnt)}%
{The file currently documented seems to be wrong.^^J%
Try to get a correct version.}%
\fi
\fi
\fi
\global\check@sum\m@ne}
% \end{macrocode}
% \end{macro}
%
%
% \begin{macro}{\check@sum}
% \changes{v1.5k}{1989/09/04}{Macro added to support checksum.}
% \begin{macro}{\bslash@cnt}
% \changes{v1.5k}{1989/09/04}{Macro added to support checksum.}
% We need to define counters, "\bslash@cnt" for the number of
% backslashes counted and "\check@sum" for the value advertised by the
% file if any. A negative value means there is no checksum checking which is the default.
% \changes{v2.1f}{2016/02/12}{Suppress \cs{CheckSum} check if no checksum
% is specified in the file}
% \begin{macrocode}
\newcount\check@sum \check@sum = \m@ne
\newcount\bslash@cnt \bslash@cnt = \z@
% \end{macrocode}
% \end{macro}
% \end{macro}
%
%
% \begin{macro}{\CheckSum}
% \changes{v1.5k}{1989/09/04}{Macro added to support checksum.}
% This is the interface to setting "\check@sum".
% \begin{macrocode}
\def\CheckSum#1{\@bsphack\global\check@sum#1\relax\@esphack}
% \end{macrocode}
% \end{macro}
%
%
%
% \begin{macro}{\step@checksum}
% \changes{v1.5k}{1989/09/04}{Macro added to support checksum.}
% This advances the count when a backslash is encountered in the
% macrocode.
% \begin{macrocode}
\def\step@checksum{\global\advance\bslash@cnt\@ne}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\CharacterTable}
% The user interface to the character table-checking does some
% "\catcode"ing and then compares the following table with the
% stored version. We need to have "@" of type ``other'' within the
% table since this is the way it is usually returned when reading
% in a normal document. To nevertheless have a private letter we
% use "~" for this purpose. "~" does no harm as a ``letter'' as it
% comes last in the table and therefore will not gobble following
% space.
% \changes{v1.5m}{1989/09/20}{Macro added to check character translation
% problems.}
% \changes{v1.5q}{1989/11/01}{Made character table more readable.}
% \changes{v1.5t}{1989/11/07}{Make \string\~{} letter in chartable
% macros.}
% \changes{v1.5u}{1989/11/14}{Made @ other in default table.}
% \begin{macrocode}
\def\CharacterTable{\begingroup \CharTableChanges \character@table}
% \end{macrocode}
% \end{macro}
% \def\MakePrivateLetters{\catcode`\~=11\makeatletter}
% \begin{macro}{\character@table}
% This does the work of comparing the tables and reporting the result.
% Note that the following code is enclosed in a group
% with "~" catcoded to letter.
% \begin{macrocode}
\begingroup
\catcode`\~=11
\gdef\character@table#1{\def\used~table{#1}%
\ifx\used~table\default~table
\typeout{***************************}%
\typeout{* Character table correct *}%
\typeout{***************************}%
\else
\PackageError{doc}{Character table corrupted}
{\the\wrong@table}
\show\default~table
\show\used~table
\fi
\endgroup}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\CharTableChanges}
% When the character table is read in we need to scan it with a
% fixed set of "\catcode"s. The reference table below was defined by
% assuming the normal "\catcode"s of \TeX{}, i.e.\ "@" is of type
% other and the only token of type ``letter'' are the usual letters
% of the alphabet. If, for some reason, other characters are made
% ``letters'' then their "\catcode"s need to be restored before
% checking the table. Otherwise spaces in the table are gobbled and
% we get the information that the tables are different, even if
% they are actually equal. For this reason "\CharTableChanges" can
% be set up to locally restore the "\catcode"s of such ``letters''
% to ``other''.
% \begin{macrocode}
\global\let\CharTableChanges\@empty
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\default~table}
% Here's what the table {\em should\/} look like (modulo spaces).
% \begin{macrocode}
\makeatother
\gdef\default~table
{Upper-case \A\B\C\D\E\F\G\H\I\J\K\L\M\N\O\P\Q\R\S\T\U\V\W\X\Y\Z
Lower-case \a\b\c\d\e\f\g\h\i\j\k\l\m\n\o\p\q\r\s\t\u\v\w\x\y\z
Digits \0\1\2\3\4\5\6\7\8\9
Exclamation \! Double quote \" Hash (number) \#
Dollar \$ Percent \% Ampersand \&
Acute accent \' Left paren \( Right paren \)
Asterisk \* Plus \+ Comma \,
Minus \- Point \. Solidus \/
Colon \: Semicolon \; Less than \<
Equals \= Greater than \> Question mark \?
Commercial at \@ Left bracket \[ Backslash \\
Right bracket \] Circumflex \^ Underscore \_
Grave accent \` Left brace \{ Vertical bar \|
Right brace \} Tilde \~}
\endgroup
% \end{macrocode}
% \end{macro}
% \let\MakePrivateLetters=\makeatletter
%
% \begin{macro}{\wrong@table}
% \changes{v1.7a}{1992/02/28}{Moved to where the catcodes are right
% so it works.}
% We need a help message in case of problems.
% \begin{macrocode}
\newhelp\wrong@table{Some of the ASCII characters are corrupted.^^J
I now \string\show\space you both tables for comparison.}
% \end{macrocode}
% \end{macro}
%
%
% \subsection[Attaching line numbers to code lines]
% {Attaching line numbers to code lines\footnotemark}
% \footnotetext{Warning: the commentary was written by Dave
% Love.}
%
%
% The code in this section allows index entries to refer to code line
% numbers---the number of the first line of macrocode in the
% \textsf{macro} environment.
%
%
% \begin{macro}{\codeline@index}
% Indexing by code line is controlled by the "codeline@index" switch.
% \changes{v1.5s}{1989/11/05}{Support for code line no. (Undoc)}
% \changes{v1.7a}{1992/02/24}{Documented code line no. support.}
% \begin{macro}{\CodelineNumbered}
% \changes{v1.8a}{1993/05/19}{Macro added}
% \begin{macrocode}
\newif\ifcodeline@index \codeline@indexfalse
\let\CodelineNumbered\codeline@indextrue
% \end{macrocode}
% \end{macro}
% \end{macro}
% \begin{macro}{\codeline@wrindex}
% The code index entries are written out by "\special@index". If
% indexing is by code line this is "\let" to "\codeline@wrindex";
% if indexing is by page it is just "\index". However, if
% "\nofiles" is given, we omit writing such an index entry at all.
% \changes{v1.7j}{1992/08/14}{Added \cs{if@filesw}.}
% \begin{macrocode}
\def\codeline@wrindex#1{\if@filesw
\immediate\write\@indexfile
{\string\indexentry{#1}%
{\number\c@CodelineNo}}\fi}
% \end{macrocode}
% \end{macro}
% \begin{macro}{\special@index}
% By default no index entries are written out.
% \begin{macrocode}
\let\special@index = \@gobble
% \end{macrocode}
% \end{macro}
% \begin{macro}{\CodelineIndex}
% \changes{v1.5u}{1989/11/14}{Added \cs{PageIndex} and
% \cs{CodelineIndex} (Undoc)}
% This switches on use of the index file with "\makeindex", sets the
% switch to indicate code line numbering and defines "\special@index"
% appropriately.
% \begin{macrocode}
\def\CodelineIndex{\makeindex
\codeline@indextrue
\let\special@index\codeline@wrindex}
% \end{macrocode}
% \end{macro}
% \begin{macro}{\PageIndex}
% "\PageIndex" is similar.
% \begin{macrocode}
\def\PageIndex{\makeindex
\codeline@indexfalse
\let\special@index\index}
% \end{macrocode}
% \end{macro}
%
%
% \begin{macro}{\c@CodelineNo}
% \changes{v1.5l}{1989/09/10}{Counter added to support code line
% numbers}
% \changes{v1.5y}{1990/02/24}{Default changed.}
% \changes{v1.6b}{1990/06/15}{\cs{rm} moved before \cs{scriptsize} to
% avoid unnecessary fontwarning.}
% We need a counter to keep track of the line number.
% \begin{macrocode}
\newcount\c@CodelineNo \c@CodelineNo\z@
% \end{macrocode}
% \end{macro}
% \begin{macro}{\theCodelineNo}
% \changes{v1.7a}{1992/02/25}{Existing definition not overwritten.}
% \changes{v1.7a}{1992/03/12}{Use \cs{reset@font} for NFSS.}
% This provides a hook to control the format of line numbers which may
% be defined in a class file.
% \begin{macrocode}
\@ifundefined{theCodelineNo}
{\ifx\selectfont\undefined
\def\theCodelineNo{\rmfamily\scriptsize\arabic{CodelineNo}}%
\else
\def\theCodelineNo{\reset@font\scriptsize\arabic{CodelineNo}}%
\fi}
{}
% \end{macrocode}
% \end{macro}
%
%
%
%
% \subsection{Layout Parameters for documenting package files}
%
% \begin{macro}{\tolerance}
% People documenting package files would probably rather have things
% ``sticking out'' in overfull |\hbox|es and poorish spacing,
% because they probably don't want to spend a lot of time on making
% all the line breaks perfect!
% \begin{macrocode}
\tolerance=1000\relax
% \end{macrocode}
% \end{macro}
%
% \DeleteShortVerb{\"}
%
% The following |\mathcode| definitions allow the characters
% `|\|'
% and `\texttt{@}' to appear in |\ttfamily| font when invoked in math
% mode;\footnote{You may wonder why the definitions state that both
% characters belong to the {\em variable family\/}
% (i.e.\ the number 7 in front). The reason is this:
% Originally the \texttt{\bslash mathcode} of
% \texttt{\bslash} was defined to be \texttt{"075C},
% i.e.\ ordinary character number 92 (hex 5C) in
% math family number 7 which is the typewriter family in
% standard \LaTeX.
% But this file should not depend on this specific
% setting, so I changed these
% \texttt{\bslash mathcode}$\,$s
% to work with any family assignments. For an example
% see the article about the new font selection scheme.}
% particularly for something like $|\@abc|=1$.
%
% If an {\em old\/} version of the \textsf{german} package is in
% force, then the `|"|' character is active and would upset the
% definition of the \meta{16-bit number} quantities below, therefore
% we change the |\catcode| of |"| inside a group, and use
% |\global|.
% \begin{macrocode}
{ \catcode`\"=12
\global\mathcode`\\="705C \global\mathcode`\@="7040 }
% \end{macrocode}
% \MakeShortVerb{\"}
%
% \begin{macro}{\DocstyleParms}
% This macro can be used, for example, to assign new values to
% |\MacrocodeTopsep| and |\MacroIndent| and some other internal
% registers. If it is already defined, the default definition
% won't be carried out. Note that it is necessary to assign new
% values via this macro if it should be done in a class file (like
% \texttt{ltugboat.cls} for example) since the registers are
% undefined before \texttt{doc.sty} is read in. The default values
% for the internal registers are scattered over this file.
% \changes{v1.5u}{1989/11/14}{\cs{DocStyleParms} now empty}
% \changes{v2.1h}{2018/02/01}{Only use\cs{DocStyleParms} if defined
% (previously the test defined it)}
% \begin{macrocode}
\@ifundefined{DocstyleParms}{}{\DocstyleParms}
% \end{macrocode}
% Clear out |\DocstyleParms| after use (or non-use).
% \begin{macrocode}
\let\DocstyleParms\relax
% \end{macrocode}
% \end{macro}
%
%
%
% \begin{macro}{\AmSTeX}
% \changes{v1.5j}{1989/06/09}{Macro AmsTeX renamed to AmSTeX}
% \begin{macro}{\BibTeX}
% \begin{macro}{\SliTeX}
% Here are a few definitions which can usefully be employed when
% documenting package files: now we can readily refer to \AmSTeX,
% \BibTeX\ and \SliTeX, as well as the usual \TeX\ and \LaTeX.
% \begin{macrocode}
\@ifundefined{AmSTeX}
{\def\AmSTeX{\leavevmode\hbox{$\mathcal A\kern-.2em\lower.376ex%
\hbox{$\mathcal M$}\kern-.2em\mathcal S$-\TeX}}}{}
\@ifundefined{BibTeX}
{\def\BibTeX{{\rmfamily B\kern-.05em%
\textsc{i\kern-.025em b}\kern-.08em%
T\kern-.1667em\lower.7ex\hbox{E}\kern-.125emX}}}{}
\@ifundefined{SliTeX}
{\def\SliTeX{{\rmfamily S\kern-.06emL\kern-.18em\raise.32ex\hbox
{\scshape i}\kern -.03em\TeX}}}{}
% \end{macrocode}
% \end{macro}
% \end{macro}
% \end{macro}
% \begin{macro}{\PlainTeX}
% \changes{v1.5g}{1989/05/07}{space between plain and TeX changed.}
% \begin{macro}{\Web}
% There's even a \PlainTeX{} and a \Web.
% \begin{macrocode}
\@ifundefined{PlainTeX}{\def\PlainTeX{\textsc{Plain}\kern2pt\TeX}}{}
\@ifundefined{Web}{\def\Web{\textsc{Web}}}{}
% \end{macrocode}
% \end{macro}
% \end{macro}
%
%
% \subsection{Changing the \texttt{\protect\bslash catcode} of \%}
%
% \begin{macro}{\MakePercentIgnore}
% \begin{macro}{\MakePercentComment}
% And finally the most important bit: we change the |\catcode|
% of `|%|' so that it is ignored (which is how we are able to
% produce this document!). We provide two commands to do the actual
% switching.
%^^A The |\MakePercentIgnore| is then called as the
%^^A last command in this file.
% \begin{macrocode}
\def\MakePercentIgnore{\catcode`\%9\relax}
\def\MakePercentComment{\catcode`\%14\relax}
% \end{macrocode}
% \end{macro}
% \end{macro}
%
% \begin{macro}{\DocInput}
% The two macros above are now used to define the |\DocInput| macro
% which was introduced in version v1.5l (or so) of the \DOC{}
% package. In older versions |\MakePercentIgnore| was placed
% at the very end of \texttt{doc.sty}.
% \begin{macrocode}
\def\DocInput#1{\MakePercentIgnore\input{#1}\MakePercentComment}
% \end{macrocode}
% \end{macro}
%
% \subsection{GetFileInfo}
%
% \begin{macro}{\GetFileInfo}
% \changes{v1.9o}{1994/05/08}{Macro added}
% \changes{v1.9z}{1997/02/05}{Missing percent latex/2404}
% Define |\filedate| and friends from info in the
% |\ProvidesPackage| etc.\ commands.
% \begin{macrocode}
\def\GetFileInfo#1{%
\def\filename{#1}%
\def\@tempb##1 ##2 ##3\relax##4\relax{%
\def\filedate{##1}%
\def\fileversion{##2}%
\def\fileinfo{##3}}%
\edef\@tempa{\csname ver@#1\endcsname}%
\expandafter\@tempb\@tempa\relax? ? \relax\relax}
% \end{macrocode}
% \end{macro}
%
% We can now finish the \texttt{docstrip} main module.
% \begin{macrocode}
%</package>
% \end{macrocode}
%
%
% \Finale
% \PrintIndex \PrintChanges
\endinput
